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Electrochemistry
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Electrochemistry Study of the interchange of chemical and electrical energy …
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Electrochemistry Study of the interchange of chemical and electrical energy … Galvanic Cells ...
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Electrochemistry Study of the interchange of chemical and electrical energy … Galvanic Cells ... Devices in which chemical energy is converted into electrical energy ...
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Electrochemistry Study of the interchange of chemical and electrical energy … Galvanic Cells ... Devices in which chemical energy is converted into electrical energy ... Cathode ...
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Electrochemistry Study of the interchange of chemical and electrical energy … Galvanic Cells ... Devices in which chemical energy is converted into electrical energy ... Cathode ... Reduction occurs here ...
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Electrochemistry Study of the interchange of chemical and electrical energy … Galvanic Cells ... Devices in which chemical energy is converted into electrical energy ... Cathode ... Reduction occurs here ... Species undergoing reduction ...
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Electrochemistry Study of the interchange of chemical and electrical energy … Galvanic Cells ... Devices in which chemical energy is converted into electrical energy ... Cathode ... Reduction occurs here ... Species undergoing reduction ... a.k.a. oxidizing agent …
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Electrochemistry Study of the interchange of chemical and electrical energy … Galvanic Cells ... Devices in which chemical energy is converted into electrical energy ... Cathode ... Reduction occurs here ... Species undergoing reduction ... a.k.a. oxidizing agent … receives electrons from the cathode ...
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Electrochemistry Study of the interchange of chemical and electrical energy … Galvanic Cells ... Devices in which chemical energy is converted into electrical energy ... Cathode ... Reduction occurs here ... Species undergoing reduction ... a.k.a. oxidizing agent … receives electrons from the cathode ... Anode ...
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Electrochemistry Study of the interchange of chemical and electrical energy … Galvanic Cells ... Devices in which chemical energy is converted into electrical energy ... Cathode ... Reduction occurs here ... Species undergoing reduction ... a.k.a. oxidizing agent … receives electrons from the cathode ... Anode ... Oxidation occurs here ...
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Electrochemistry Study of the interchange of chemical and electrical energy … Galvanic Cells ... Devices in which chemical energy is converted into electrical energy ... Cathode ... Reduction occurs here ... Species undergoing reduction ... a.k.a. oxidizing agent … receives electrons from the cathode ... Anode ... Oxidation occurs here ... aka reducing agent …
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Electrochemistry Study of the interchange of chemical and electrical energy … Galvanic Cells ... Devices in which chemical energy is converted into electrical energy ... Cathode ... Reduction occurs here ... Species undergoing reduction ... a.k.a. oxidizing agent … receives electrons from the cathode ... Anode ... Oxidation occurs here ... aka reducing agent … gives up electrons to cathode here ...
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Electrochemistry Study of the interchange of chemical and electrical energy … Galvanic Cells ... Devices in which chemical energy is converted into electrical energy ... Cathode ... Reduction occurs here ... Species undergoing reduction ... a.k.a. oxidizing agent … receives electrons from the cathode ... Anode ... Oxidation occurs here ... aka reducing agent … gives up electrons to cathode here ... Salt bridge
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Electrochemistry Study of the interchange of chemical and electrical energy … Galvanic Cells ... Devices in which chemical energy is converted into electrical energy ... Cathode ... Reduction occurs here ... Species undergoing reduction ... a.k.a. oxidizing agent … receives electrons from the cathode ... Anode ... Oxidation occurs here ... aka reducing agent … gives up electrons to cathode here ... Salt bridge (or porous disk) …
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Electrochemistry Study of the interchange of chemical and electrical energy … Galvanic Cells ... Devices in which chemical energy is converted into electrical energy ... Cathode ... Reduction occurs here ... Species undergoing reduction ... a.k.a. oxidizing agent … receives electrons from the cathode ... Anode ... Oxidation occurs here ... aka reducing agent … gives up electrons to cathode here ... Salt bridge (or porous disk) … allows flow of electrons to keep electrical neutrality ...
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Electrochemistry Study of the interchange of chemical and electrical energy … Galvanic Cells ... Devices in which chemical energy is converted into electrical energy ... Cathode ... Reduction occurs here ... Species undergoing reduction ... a.k.a. oxidizing agent … receives electrons from the cathode ... Anode ... Oxidation occurs here ... aka reducing agent … gives up electrons to cathode here ... Salt bridge (or porous disk) … allows flow of electrons to keep electrical neutrality ... electroactve solutions remain separated …
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Electrochemistry Study of the interchange of chemical and electrical energy … Galvanic Cells ... Devices in which chemical energy is converted into electrical energy ... Cathode ... Reduction occurs here ... Species undergoing reduction ... a.k.a. oxidizing agent … receives electrons from the cathode ... Anode ... Oxidation occurs here ... aka reducing agent … gives up electrons to cathode here ... Salt bridge (or porous disk) … allows flow of electrons to keep electrical neutrality ... electroactve solutions remain separated … Electromotive force (emf) ...
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Electrochemistry Study of the interchange of chemical and electrical energy … Galvanic Cells ... Devices in which chemical energy is converted into electrical energy ... Cathode ... Reduction occurs here ... Species undergoing reduction ... a.k.a. oxidizing agent … receives electrons from the cathode ... Anode ... Oxidation occurs here ... aka reducing agent … gives up electrons to cathode here ... Salt bridge (or porous disk) … allows flow of electrons to keep electrical neutrality ... electroactve solutions remain separated … Electromotive force (emf) ...
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Electrochemistry Study of the interchange of chemical and electrical energy … Galvanic Cells ... Devices in which chemical energy is converted into electrical energy ... Cathode ... Reduction occurs here ... Species undergoing reduction ... a.k.a. oxidizing agent … receives electrons from the cathode ... Anode ... Oxidation occurs here ... aka reducing agent … gives up electrons to cathode here ... Salt bridge (or porous disk) … allows flow of electrons to keep electrical neutrality ... electroactve solutions remain separated … Electromotive force (emf) ... the driving force with which electrons are pulled through a wire ...
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Electrochemistry Study of the interchange of chemical and electrical energy … Galvanic Cells ... Devices in which chemical energy is converted into electrical energy ... Cathode ... Reduction occurs here ... Species undergoing reduction ... a.k.a. oxidizing agent … receives electrons from the cathode ... Anode ... Oxidation occurs here ... aka reducing agent … gives up electrons to cathode here ... Salt bridge (or porous disk) … allows flow of electrons to keep electrical neutrality ... electroactve solutions remain separated … Electromotive force (emf) ... the driving force with which electrons are pulled through a wire ... Volt (V) ...
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Electrochemistry Study of the interchange of chemical and electrical energy … Galvanic Cells ... Devices in which chemical energy is converted into electrical energy ... Cathode ... Reduction occurs here ... Species undergoing reduction ... a.k.a. oxidizing agent … receives electrons from the cathode ... Anode ... Oxidation occurs here ... aka reducing agent … gives up electrons to cathode here ... Salt bridge (or porous disk) … allows flow of electrons to keep electrical neutrality ... electroactve solutions remain separated … Electromotive force (emf) ... the driving force with which electrons are pulled through a wire ... Volt (V) ... the unit of electrical potential …
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Electrochemistry Study of the interchange of chemical and electrical energy … Galvanic Cells ... Devices in which chemical energy is converted into electrical energy ... Cathode ... Reduction occurs here ... Species undergoing reduction ... a.k.a. oxidizing agent … receives electrons from the cathode ... Anode ... Oxidation occurs here ... aka reducing agent … gives up electrons to cathode here ... Salt bridge (or porous disk) … allows flow of electrons to keep electrical neutrality ... electroactve solutions remain separated … Electromotive force (emf) ... the driving force with which electrons are pulled through a wire ... Volt (V) ... the unit of electrical potential … it equals 1 Joule/coulomb ...
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Electrochemistry Direction of electron flow in Galvanic Cells …
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Electrochemistry Direction of electron flow in Galvanic Cells … From anaode to cathode ...
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Electrochemistry Direction of electron flow in Galvanic Cells … From anaode to cathode ... FATCAT ...
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Electrochemistry Direction of electron flow in Galvanic Cells … From anode to cathode ... FATCAT ... Species undergoing reduction receive electrons from the cathode ...
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Electrochemistry Direction of electron flow in Galvanic Cells … From anode to cathode ... FATCAT ... Species undergoing reduction receive electrons from the cathode ... Species undergoing oxidation donate electrons to the anode ...
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Electrochemistry Direction of electron flow in Galvanic Cells … From anode to cathode ... FATCAT ... Species undergoing reduction receive electrons from the cathode ... Species undergoing oxidation donate electrons to the anode ... Known: a. Mg(s) + 2H+(aq) ----> Mg+2(aq) + H2(g)
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Electrochemistry Direction of electron flow in Galvanic Cells … From anode to cathode ... FATCAT ... Species undergoing reduction receive electrons from the cathode ... Species undergoing oxidation donate electrons to the anode ... Known: a. Mg(s) + 2H+(aq) ----> Mg+2(aq) + H2(g) b. MnO4-1(aq) + 5Fe+2(aq) + 8H+(aq) ---> Mn+2(aq) + 5Fe+3(aq) + 4H2O(l)
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Electrochemistry Direction of electron flow in Galvanic Cells … From anode to cathode ... FATCAT ... Species undergoing reduction receive electrons from the cathode ... Species undergoing oxidation donate electrons to the anode ... Known: a. Mg(s) + 2H+(aq) ----> Mg+2(aq) + H2(g) b. MnO4-1(aq) + 5Fe+2(aq) + 8H+(aq) ---> Mn+2(aq) + 5Fe+3(aq) + 4H2O(l) Unknown:
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Electrochemistry Direction of electron flow in Galvanic Cells … From anode to cathode ... FATCAT ... Species undergoing reduction receive electrons from the cathode ... Species undergoing oxidation donate electrons to the anode ... Known: a. Mg(s) + 2H+(aq) ----> Mg+2(aq) + H2(g) b. MnO4-1(aq) + 5Fe+2(aq) + 8H+(aq) ---> Mn+2(aq) + 5Fe+3(aq) + 4H2O(l) Unknown: Identify the species that would receive electrons from the cathode and which would lose electrons at the anode in each of the following galvanic cells ...
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Electrochemistry Direction of electron flow in Galvanic Cells … From anode to cathode ... FATCAT ... Species undergoing reduction receive electrons from the cathode ... Species undergoing oxidation donate electrons to the anode ... Known: a. Mg(s) + 2H+(aq) ----> Mg+2(aq) + H2(g) b. MnO4-1(aq) + 5Fe+2(aq) + 8H+(aq) ---> Mn+2(aq) + 5Fe+3(aq) + 4H2O(l) Unknown: Identify the species that would receive electrons from the cathode and which would lose electrons at the anode in each of the following galvanic cells ... Solution:
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Electrochemistry Direction of electron flow in Galvanic Cells … From anode to cathode ... FATCAT ... Species undergoing reduction receive electrons from the cathode ... Species undergoing oxidation donate electrons to the anode ... Known: a. Mg(s) + 2H+(aq) ----> Mg+2(aq) + H2(g) b. MnO4-1(aq) + 5Fe+2(aq) + 8H+(aq) ---> Mn+2(aq) + 5Fe+3(aq) + 4H2O(l) Unknown: Identify the species that would receive electrons from the cathode and which would lose electrons at the anode in each of the following galvanic cells ... Solution: reduction ½ rxs receive e-1 at cathode ...
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Electrochemistry Direction of electron flow in Galvanic Cells … From anode to cathode ... FATCAT ... Species undergoing reduction receive electrons from the cathode ... Species undergoing oxidation donate electrons to the anode ... Known: a. Mg(s) + 2H+(aq) ----> Mg+2(aq) + H2(g) b. MnO4-1(aq) + 5Fe+2(aq) + 8H+(aq) ---> Mn+2(aq) + 5Fe+3(aq) + 4H2O(l) Unknown: Identify the species that would receive electrons from the cathode and which would lose electrons at the anode in each of the following galvanic cells ... Solution: reduction ½ rxs receive cathode ... oxidation ½ rxs. lose anode ...
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Electrochemistry Known: a. Mg(s) + 2H+(aq) ----> Mg+2(aq) + H2(g)
b. MnO4-1(aq) + 5Fe+2(aq) + 8H+(aq) ---> Mn+2(aq) + 5Fe+3(aq) + 4H2O(l) Unknown: Identify the species that would receive electrons from the cathode and which would lose electrons at the anode in each of the following galvanic cells ... Solution: reduction ½ rxs receive cathode ... oxidation ½ rxs. lose anode ... a. Oxidation (anode):
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Electrochemistry Known: a. Mg(s) + 2H+(aq) ----> Mg+2(aq) + H2(g)
b. MnO4-1(aq) + 5Fe+2(aq) + 8H+(aq) ---> Mn+2(aq) + 5Fe+3(aq) + 4H2O(l) Unknown: Identify the species that would receive electrons from the cathode and which would lose electrons at the anode in each of the following galvanic cells ... Solution: reduction ½ rxs receive cathode ... oxidation ½ rxs. lose anode ... a. Oxidation (anode): Mg(s) ----> Mg+2(aq) + 2e-1
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Electrochemistry Known: a. Mg(s) + 2H+(aq) ----> Mg+2(aq) + H2(g)
b. MnO4-1(aq) + 5Fe+2(aq) + 8H+(aq) ---> Mn+2(aq) + 5Fe+3(aq) + 4H2O(l) Unknown: Identify the species that would receive electrons from the cathode and which would lose electrons at the anode in each of the following galvanic cells ... Solution: reduction ½ rxs receive cathode ... oxidation ½ rxs. lose anode ... a. Oxidation (anode): Mg(s) ----> Mg+2(aq) + 2e-1 Reduction (cathode):
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Electrochemistry Known: a. Mg(s) + 2H+(aq) ----> Mg+2(aq) + H2(g)
b. MnO4-1(aq) + 5Fe+2(aq) + 8H+(aq) ---> Mn+2(aq) + 5Fe+3(aq) + 4H2O(l) Unknown: Identify the species that would receive electrons from the cathode and which would lose electrons at the anode in each of the following galvanic cells ... Solution: reduction ½ rxs receive cathode ... oxidation ½ rxs. lose anode ... a. Oxidation (anode): Mg(s) ----> Mg+2(aq) + 2e-1 Reduction (cathode): 2H+(aq) + 2e > H2(g)
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Electrochemistry Known: a. Mg(s) + 2H+(aq) ----> Mg+2(aq) + H2(g)
b. MnO4-1(aq) + 5Fe+2(aq) + 8H+(aq) ---> Mn+2(aq) + 5Fe+3(aq) + 4H2O(l) Unknown: Identify the species that would receive electrons from the cathode and which would lose electrons at the anode in each of the following galvanic cells ... Solution: reduction ½ rxs receive cathode ... oxidation ½ rxs. lose anode ... a. Oxidation (anode): Mg(s) ----> Mg+2(aq) + 2e-1 Reduction (cathode): 2H+(aq) + 2e > H2(g)
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Electrochemistry Known: a. Mg(s) + 2H+(aq) ----> Mg+2(aq) + H2(g)
b. MnO4-1(aq) + 5Fe+2(aq) + 8H+(aq) ---> Mn+2(aq) + 5Fe+3(aq) + 4H2O(l) Unknown: Identify the species that would receive electrons from the cathode and which would lose electrons at the anode in each of the following galvanic cells ... Solution: reduction ½ rxs receive cathode ... oxidation ½ rxs. lose anode ... a. Oxidation (anode): Mg(s) ----> Mg+2(aq) + 2e-1 Reduction (cathode): 2H+(aq) + 2e > H2(g) b. Oxidation (anode):
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Electrochemistry Known: a. Mg(s) + 2H+(aq) ----> Mg+2(aq) + H2(g)
b. MnO4-1(aq) + 5Fe+2(aq) + 8H+(aq) ---> Mn+2(aq) + 5Fe+3(aq) + 4H2O(l) Unknown: Identify the species that would receive electrons from the cathode and which would lose electrons at the anode in each of the following galvanic cells ... Solution: reduction ½ rxs receive cathode ... oxidation ½ rxs. lose anode ... a. Oxidation (anode): Mg(s) ----> Mg+2(aq) + 2e-1 Reduction (cathode): 2H+(aq) + 2e > H2(g) b. Oxidation (anode): 5Fe+2(aq) ----> 5Fe+3(aq) + 5e-1
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Electrochemistry Known: a. Mg(s) + 2H+(aq) ----> Mg+2(aq) + H2(g)
b. MnO4-1(aq) + 5Fe+2(aq) + 8H+(aq) ---> Mn+2(aq) + 5Fe+3(aq) + 4H2O(l) Unknown: Identify the species that would receive electrons from the cathode and which would lose electrons at the anode in each of the following galvanic cells ... Solution: reduction ½ rxs receive cathode ... oxidation ½ rxs. lose anode ... a. Oxidation (anode): Mg(s) ----> Mg+2(aq) + 2e-1 Reduction (cathode): 2H+(aq) + 2e > H2(g) b. Oxidation (anode): 5Fe+2(aq) ----> 5Fe+3(aq) + 5e-1 Reduction (cathode):
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Electrochemistry Known: a. Mg(s) + 2H+(aq) ----> Mg+2(aq) + H2(g)
b. MnO4-1(aq) + 5Fe+2(aq) + 8H+(aq) ---> Mn+2(aq) + 5Fe+3(aq) + 4H2O(l) Unknown: Identify the species that would receive electrons from the cathode and which would lose electrons at the anode in each of the following galvanic cells ... Solution: reduction ½ rxs receive cathode ... oxidation ½ rxs. lose anode ... a. Oxidation (anode): Mg(s) ----> Mg+2(aq) + 2e-1 Reduction (cathode): 2H+(aq) + 2e > H2(g) b. Oxidation (anode): 5Fe+2(aq) ----> 5Fe+3(aq) + 5e-1 Reduction (cathode): MnO4-1(aq) + 8H+(aq) + 5e > Mn+2(aq) + 4H2O(l)
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Electrochemistry Standard Reduction Potentials …
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Electrochemistry Standard Reduction Potentials …
Electromotive force (emf) of a galvanic cell is a combination of the potentials of the two half-reactions ...
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Electrochemistry Standard Reduction Potentials …
Electromotive force (emf) of a galvanic cell is a combination of the potentials of the two half-reactions ... Cathodic potentials are described relative to anodic reactions ...
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Electrochemistry Standard Reduction Potentials …
Electromotive force (emf) of a galvanic cell is a combination of the potentials of the two half-reactions ... Cathodic potentials are described relative to anodic reactions ... An absolute standard against which all other half-reactions can be compared is required ...
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Electrochemistry Standard Reduction Potentials …
Electromotive force (emf) of a galvanic cell is a combination of the potentials of the two half-reactions ... Cathodic potentials are described relative to anodic reactions ... An absolute standard against which all other half-reactions can be compared is required ... The standard is the standard hydrogen electrode ...
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2H+(aq) + 2e-1 ---> H2(g) E’ = 0.00 V
Electrochemistry Standard Reduction Potentials … Electromotive force (emf) of a galvanic cell is a combination of the potentials of the two half-reactions ... Cathodic potentials are described relative to anodic reactions ... An absolute standard against which all other half-reactions can be compared is required ... The standard is the standard hydrogen electrode ... 2H+(aq) + 2e-1 ---> H2(g) E’ = 0.00 V
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2H+(aq) + 2e-1 ---> H2(g) E’ = 0.00 V (exactly, by definition)
Electrochemistry Standard Reduction Potentials … Electromotive force (emf) of a galvanic cell is a combination of the potentials of the two half-reactions ... Cathodic potentials are described relative to anodic reactions ... An absolute standard against which all other half-reactions can be compared is required ... The standard is the standard hydrogen electrode ... 2H+(aq) + 2e-1 ---> H2(g) E’ = 0.00 V (exactly, by definition)
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2H+(aq) + 2e-1 ---> H2(g) E’ = 0.00 V (exactly, by definition)
Electrochemistry Standard Reduction Potentials … Electromotive force (emf) of a galvanic cell is a combination of the potentials of the two half-reactions ... Cathodic potentials are described relative to anodic reactions ... An absolute standard against which all other half-reactions can be compared is required ... The standard is the standard hydrogen electrode K & 1 atm ... 2H+(aq) + 2e-1 ---> H2(g) E’ = 0.00 V (exactly, by definition)
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2H+(aq) + 2e-1 ---> H2(g) E’ = 0.00 V (exactly, by definition)
Electrochemistry Standard Reduction Potentials … Electromotive force (emf) of a galvanic cell is a combination of the potentials of the two half-reactions ... Cathodic potentials are described relative to anodic reactions ... An absolute standard against which all other half-reactions can be compared is required ... The standard is the standard hydrogen electrode K & 1 atm ... 2H+(aq) + 2e-1 ---> H2(g) E’ = 0.00 V (exactly, by definition) Galvanic cells require E’cell > 0 ...
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2H+(aq) + 2e-1 ---> H2(g) E’ = 0.00 V (exactly, by definition)
Electrochemistry Standard Reduction Potentials … Electromotive force (emf) of a galvanic cell is a combination of the potentials of the two half-reactions ... Cathodic potentials are described relative to anodic reactions ... An absolute standard against which all other half-reactions can be compared is required ... The standard is the standard hydrogen electrode K & 1 atm ... 2H+(aq) + 2e-1 ---> H2(g) E’ = 0.00 V (exactly, by definition) Galvanic cells require E’cell > 0 ... One of the tabulated cell potentials have to be reversed ...
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2H+(aq) + 2e-1 ---> H2(g) E’ = 0.00 V (exactly, by definition)
Electrochemistry Standard Reduction Potentials … Electromotive force (emf) of a galvanic cell is a combination of the potentials of the two half-reactions ... Cathodic potentials are described relative to anodic reactions ... An absolute standard against which all other half-reactions can be compared is required ... The standard is the standard hydrogen electrode K & 1 atm ... 2H+(aq) + 2e-1 ---> H2(g) E’ = 0.00 V (exactly, by definition) Galvanic cells require E’cell > 0 ... One of the tabulated cell potentials have to be reversed ... to form an oxidation half-reaction in EVERY E’ calculation …
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2H+(aq) + 2e-1 ---> H2(g) E’ = 0.00 V (exactly, by definition)
Electrochemistry The standard is the standard hydrogen electrode K & 1 atm ... 2H+(aq) + 2e-1 ---> H2(g) E’ = 0.00 V (exactly, by definition) Galvanic cells require E’cell > 0 ... One of the tabulated cell potentials have to be reversed ... to form an oxidation half-reaction in EVERY E’ calculation …
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2H+(aq) + 2e-1 ---> H2(g) E’ = 0.00 V (exactly, by definition)
Electrochemistry The standard is the standard hydrogen electrode K & 1 atm ... 2H+(aq) + 2e-1 ---> H2(g) E’ = 0.00 V (exactly, by definition) Galvanic cells require E’cell > 0 ... One of the tabulated cell potentials have to be reversed ... to form an oxidation half-reaction in EVERY E’ calculation … To determine which reaction is to be reversed ...
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2H+(aq) + 2e-1 ---> H2(g) E’ = 0.00 V (exactly, by definition)
Electrochemistry The standard is the standard hydrogen electrode K & 1 atm ... 2H+(aq) + 2e-1 ---> H2(g) E’ = 0.00 V (exactly, by definition) Galvanic cells require E’cell > 0 ... One of the tabulated cell potentials have to be reversed ... to form an oxidation half-reaction in EVERY E’ calculation … To determine which reaction is to be reversed ... the sum of the oxidation and reduction half-reactions must be > 0 in a galvanic cell …
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2H+(aq) + 2e-1 ---> H2(g) E’ = 0.00 V (exactly, by definition)
Electrochemistry The standard is the standard hydrogen electrode K & 1 atm ... 2H+(aq) + 2e-1 ---> H2(g) E’ = 0.00 V (exactly, by definition) Galvanic cells require E’cell > 0 ... One of the tabulated cell potentials have to be reversed ... to form an oxidation half-reaction in EVERY E’ calculation … To determine which reaction is to be reversed ... the sum of the oxidation and reduction half-reactions must be > 0 in a galvanic cell … When you reverse a reaction ...
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2H+(aq) + 2e-1 ---> H2(g) E’ = 0.00 V (exactly, by definition)
Electrochemistry The standard is the standard hydrogen electrode K & 1 atm ... 2H+(aq) + 2e-1 ---> H2(g) E’ = 0.00 V (exactly, by definition) Galvanic cells require E’cell > 0 ... One of the tabulated cell potentials have to be reversed ... to form an oxidation half-reaction in EVERY E’ calculation … To determine which reaction is to be reversed ... the sum of the oxidation and reduction half-reactions must be > 0 in a galvanic cell … When you reverse a reaction ... E’ gets the opposite sign ...
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2H+(aq) + 2e-1 ---> H2(g) E’ = 0.00 V (exactly, by definition)
Electrochemistry The standard is the standard hydrogen electrode K & 1 atm ... 2H+(aq) + 2e-1 ---> H2(g) E’ = 0.00 V (exactly, by definition) Galvanic cells require E’cell > 0 ... One of the tabulated cell potentials have to be reversed ... to form an oxidation half-reaction in EVERY E’ calculation … To determine which reaction is to be reversed ... the sum of the oxidation and reduction half-reactions must be > 0 in a galvanic cell … When you reverse a reaction ... E’ gets the opposite sign ... When you multiply a reaction by a coefficient (for purposes of balancing) ...
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2H+(aq) + 2e-1 ---> H2(g) E’ = 0.00 V (exactly, by definition)
Electrochemistry The standard is the standard hydrogen electrode K & 1 atm ... 2H+(aq) + 2e-1 ---> H2(g) E’ = 0.00 V (exactly, by definition) Galvanic cells require E’cell > 0 ... One of the tabulated cell potentials have to be reversed ... to form an oxidation half-reaction in EVERY E’ calculation … To determine which reaction is to be reversed ... the sum of the oxidation and reduction half-reactions must be > 0 in a galvanic cell … When you reverse a reaction ... E’ gets the opposite sign ... When you multiply a reaction by a coefficient (for purposes of balancing) ... E’ is not changed ...
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Electrochemistry Cell Emf …
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Electrochemistry Cell Emf … Known:
a. Mg(s) + 2H+(aq) ----> Mg+2(aq) + H2(g)
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Electrochemistry Cell Emf … Known:
Mg(s) + 2H+(aq) ----> Mg+2(aq) + H2(g) Cu+2(aq) + 2Ag(s) ----> Cu(s) + 2Ag+1(aq)
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Electrochemistry Cell Emf … Known:
a. Mg(s) + 2H+(aq) ----> Mg+2(aq) + H2(g) b. Cu+2(aq) + 2Ag(s) ----> Cu(s) + 2Ag+1(aq) c. 2Zn+2(aq) + 4OH-1(aq) ----> 2Zn(aq) + O2(g) + 2H2O(l)
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Electrochemistry Cell Emf … Known: Unknown:
a. Mg(s) + 2H+(aq) ----> Mg+2(aq) + H2(g) E’cell = ? V b. Cu+2(aq) + 2Ag(s) ----> Cu(s) + 2Ag+1(aq) c. 2Zn+2(aq) + 4OH-1(aq) ----> 2Zn(aq) + O2(g) + 2H2O(l)
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Electrochemistry Cell Emf … Known: Unknown:
a. Mg(s) + 2H+(aq) ----> Mg+2(aq) + H2(g) E’cell = ? V b. Cu+2(aq) + 2Ag(s) ----> Cu(s) + 2Ag+1(aq) Galvanic? c. 2Zn+2(aq) + 4OH-1(aq) ----> 2Zn(aq) + O2(g) + 2H2O(l)
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Electrochemistry Cell Emf … Known: Unknown:
a. Mg(s) + 2H+(aq) ----> Mg+2(aq) + H2(g) E’cell = ? V b. Cu+2(aq) + 2Ag(s) ----> Cu(s) + 2Ag+1(aq) Galvanic? c. 2Zn+2(aq) + 4OH-1(aq) ----> 2Zn(aq) + O2(g) + 2H2O(l) Solution:
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Electrochemistry Cell Emf … Known: Unknown:
a. Mg(s) + 2H+(aq) ----> Mg+2(aq) + H2(g) E’cell = ? V b. Cu+2(aq) + 2Ag(s) ----> Cu(s) + 2Ag+1(aq) Galvanic? c. 2Zn+2(aq) + 4OH-1(aq) ----> 2Zn(aq) + O2(g) + 2H2O(l) Solution: Split each rx into two ½ rxs …
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Electrochemistry Cell Emf … Known: Unknown:
a. Mg(s) + 2H+(aq) ----> Mg+2(aq) + H2(g) E’cell = ? V b. Cu+2(aq) + 2Ag(s) ----> Cu(s) + 2Ag+1(aq) Galvanic? c. 2Zn+2(aq) + 4OH-1(aq) ----> 2Zn(aq) + O2(g) + 2H2O(l) Solution: Split each rx into two ½ rxs … look up cell potentials ...
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Electrochemistry Cell Emf … Known: Unknown:
a. Mg(s) + 2H+(aq) ----> Mg+2(aq) + H2(g) E’cell = ? V b. Cu+2(aq) + 2Ag(s) ----> Cu(s) + 2Ag+1(aq) Galvanic? c. 2Zn+2(aq) + 4OH-1(aq) ----> 2Zn(aq) + O2(g) + 2H2O(l) Solution: Split each rx into two ½ rxs … look up cell potentials ... a. reduction:
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Electrochemistry Cell Emf … Known: Unknown:
a. Mg(s) + 2H+(aq) ----> Mg+2(aq) + H2(g) E’cell = ? V b. Cu+2(aq) + 2Ag(s) ----> Cu(s) + 2Ag+1(aq) Galvanic? c. 2Zn+2(aq) + 4OH-1(aq) ----> 2Zn(aq) + O2(g) + 2H2O(l) Solution: Split each rx into two ½ rxs … look up cell potentials ... a. reduction: 2H+(aq) + 2e > H2(g)
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Electrochemistry Cell Emf … Known: Unknown:
a. Mg(s) + 2H+(aq) ----> Mg+2(aq) + H2(g) E’cell = ? V b. Cu+2(aq) + 2Ag(s) ----> Cu(s) + 2Ag+1(aq) Galvanic? c. 2Zn+2(aq) + 4OH-1(aq) ----> 2Zn(aq) + O2(g) + 2H2O(l) Solution: Split each rx into two ½ rxs … look up cell potentials ... a. reduction: 2H+(aq) + 2e > H2(g) E’ = 0.00 V
75
Electrochemistry Cell Emf … Known: Unknown:
a. Mg(s) + 2H+(aq) ----> Mg+2(aq) + H2(g) E’cell = ? V b. Cu+2(aq) + 2Ag(s) ----> Cu(s) + 2Ag+1(aq) Galvanic? c. 2Zn+2(aq) + 4OH-1(aq) ----> 2Zn(aq) + O2(g) + 2H2O(l) Solution: Split each rx into two ½ rxs … look up cell potentials ... a. reduction: 2H+(aq) + 2e > H2(g) E’ = 0.00 V oxidation: Mg(s) ----> Mg+2(aq) + 2e-1
76
Electrochemistry Cell Emf … Known: Unknown:
a. Mg(s) + 2H+(aq) ----> Mg+2(aq) + H2(g) E’cell = ? V b. Cu+2(aq) + 2Ag(s) ----> Cu(s) + 2Ag+1(aq) Galvanic? c. 2Zn+2(aq) + 4OH-1(aq) ----> 2Zn(aq) + O2(g) + 2H2O(l) Solution: Split each rx into two ½ rxs … look up cell potentials ... a. reduction: 2H+(aq) + 2e > H2(g) E’ = 0.00 V oxidation: Mg(s) ----> Mg+2(aq) + 2e-1 E’ = V
77
Electrochemistry Cell Emf … Known: Unknown:
a. Mg(s) + 2H+(aq) ----> Mg+2(aq) + H2(g) E’cell = ? V b. Cu+2(aq) + 2Ag(s) ----> Cu(s) + 2Ag+1(aq) Galvanic? c. 2Zn+2(aq) + 4OH-1(aq) ----> 2Zn(aq) + O2(g) + 2H2O(l) Solution: Split each rx into two ½ rxs … look up cell potentials ... a. reduction: 2H+(aq) + 2e > H2(g) E’ = V oxidation: Mg(s) ----> Mg+2(aq) + 2e-1 E’ = V E’cell = V
78
Electrochemistry Cell Emf … Known: Unknown:
a. Mg(s) + 2H+(aq) ----> Mg+2(aq) + H2(g) E’cell = ? V b. Cu+2(aq) + 2Ag(s) ----> Cu(s) + 2Ag+1(aq) Galvanic? c. 2Zn+2(aq) + 4OH-1(aq) ----> 2Zn(aq) + O2(g) + 2H2O(l) Solution: Split each rx into two ½ rxs … look up cell potentials ... a. reduction: 2H+(aq) + 2e > H2(g) E’ = V oxidation: Mg(s) ----> Mg+2(aq) + 2e-1 E’ = V E’cell = V (Galvanic)
79
Electrochemistry Cell Emf … Known: Unknown:
a. Mg(s) + 2H+(aq) ----> Mg+2(aq) + H2(g) E’cell = ? V b. Cu+2(aq) + 2Ag(s) ----> Cu(s) + 2Ag+1(aq) Galvanic? c. 2Zn+2(aq) + 4OH-1(aq) ----> 2Zn(aq) + O2(g) + 2H2O(l) Solution: Split each rx into two ½ rxs … look up cell potentials ... a. reduction: 2H+(aq) + 2e > H2(g) E’ = V oxidation: Mg(s) ----> Mg+2(aq) + 2e-1 E’ = V E’cell = V (Galvanic) b. reduction: Cu+2(aq) + 2e > Cu(s)
80
Electrochemistry Cell Emf … Known: Unknown:
a. Mg(s) + 2H+(aq) ----> Mg+2(aq) + H2(g) E’cell = ? V b. Cu+2(aq) + 2Ag(s) ----> Cu(s) + 2Ag+1(aq) Galvanic? c. 2Zn+2(aq) + 4OH-1(aq) ----> 2Zn(aq) + O2(g) + 2H2O(l) Solution: Split each rx into two ½ rxs … look up cell potentials ... a. reduction: 2H+(aq) + 2e > H2(g) E’ = V oxidation: Mg(s) ----> Mg+2(aq) + 2e-1 E’ = V E’cell = V (Galvanic) b. reduction: Cu+2(aq) + 2e > Cu(s) E’ = V
81
Electrochemistry Cell Emf … Known: Unknown:
a. Mg(s) + 2H+(aq) ----> Mg+2(aq) + H2(g) E’cell = ? V b. Cu+2(aq) + 2Ag(s) ----> Cu(s) + 2Ag+1(aq) Galvanic? c. 2Zn+2(aq) + 4OH-1(aq) ----> 2Zn(aq) + O2(g) + 2H2O(l) Solution: Split each rx into two ½ rxs … look up cell potentials ... a. reduction: 2H+(aq) + 2e > H2(g) E’ = V oxidation: Mg(s) ----> Mg+2(aq) + 2e-1 E’ = V E’cell = V (Galvanic) b. reduction: Cu+2(aq) + 2e > Cu(s) E’ = V oxidation: 2Ag(s) ----> 2Ag+1(aq) + 2e-1
82
Electrochemistry Cell Emf … Known: Unknown:
a. Mg(s) + 2H+(aq) ----> Mg+2(aq) + H2(g) E’cell = ? V b. Cu+2(aq) + 2Ag(s) ----> Cu(s) + 2Ag+1(aq) Galvanic? c. 2Zn+2(aq) + 4OH-1(aq) ----> 2Zn(aq) + O2(g) + 2H2O(l) Solution: Split each rx into two ½ rxs … look up cell potentials ... a. reduction: 2H+(aq) + 2e > H2(g) E’ = V oxidation: Mg(s) ----> Mg+2(aq) + 2e-1 E’ = V E’cell = V (Galvanic) b. reduction: Cu+2(aq) + 2e > Cu(s) E’ = V oxidation: 2Ag(s) ----> 2Ag+1(aq) + 2e-1 E’ = V
83
Electrochemistry Cell Emf … Known: Unknown:
a. Mg(s) + 2H+(aq) ----> Mg+2(aq) + H2(g) E’cell = ? V b. Cu+2(aq) + 2Ag(s) ----> Cu(s) + 2Ag+1(aq) Galvanic? c. 2Zn+2(aq) + 4OH-1(aq) ----> 2Zn(aq) + O2(g) + 2H2O(l) Solution: Split each rx into two ½ rxs … look up cell potentials ... a. reduction: 2H+(aq) + 2e > H2(g) E’ = V oxidation: Mg(s) ----> Mg+2(aq) + 2e-1 E’ = V E’cell = V (Galvanic) b. reduction: Cu+2(aq) + 2e > Cu(s) E’ = V oxidation: 2Ag(s) ----> 2Ag+1(aq) + 2e-1 E’ = V
84
Electrochemistry Cell Emf … Known: Unknown:
a. Mg(s) + 2H+(aq) ----> Mg+2(aq) + H2(g) E’cell = ? V b. Cu+2(aq) + 2Ag(s) ----> Cu(s) + 2Ag+1(aq) Galvanic? c. 2Zn+2(aq) + 4OH-1(aq) ----> 2Zn(aq) + O2(g) + 2H2O(l) Solution: Split each rx into two ½ rxs … look up cell potentials ... a. reduction: 2H+(aq) + 2e > H2(g) E’ = V oxidation: Mg(s) ----> Mg+2(aq) + 2e-1 E’ = V E’cell = V (Galvanic) b. reduction: Cu+2(aq) + 2e > Cu(s) E’ = V oxidation: 2Ag(s) ----> 2Ag+1(aq) + 2e-1 E’ = V E’cell = V
85
Electrochemistry Cell Emf … Known: Unknown:
a. Mg(s) + 2H+(aq) ----> Mg+2(aq) + H2(g) E’cell = ? V b. Cu+2(aq) + 2Ag(s) ----> Cu(s) + 2Ag+1(aq) Galvanic? c. 2Zn+2(aq) + 4OH-1(aq) ----> 2Zn(aq) + O2(g) + 2H2O(l) Solution: Split each rx into two ½ rxs … look up cell potentials ... a. reduction: 2H+(aq) + 2e > H2(g) E’ = V oxidation: Mg(s) ----> Mg+2(aq) + 2e-1 E’ = V E’cell = V (Galvanic) b. reduction: Cu+2(aq) + 2e > Cu(s) E’ = V oxidation: 2Ag(s) ----> 2Ag+1(aq) + 2e-1 E’ = V E’cell = V (Not Galvanic)
86
Electrochemistry Cell Emf … Known: Unknown:
a. Mg(s) + 2H+(aq) ----> Mg+2(aq) + H2(g) E’cell = ? V b. Cu+2(aq) + 2Ag(s) ----> Cu(s) + 2Ag+1(aq) Galvanic? c. 2Zn+2(aq) + 4OH-1(aq) ----> 2Zn(aq) + O2(g) + 2H2O(l) Solution: Split each rx into two ½ rxs … look up cell potentials ... a. reduction: 2H+(aq) + 2e > H2(g) E’ = V oxidation: Mg(s) ----> Mg+2(aq) + 2e-1 E’ = V E’cell = V (Galvanic) b. reduction: Cu+2(aq) + 2e > Cu(s) E’ = V oxidation: 2Ag(s) ----> 2Ag+1(aq) + 2e-1 E’ = V E’cell = V (Not Galvanic) Note: will not run in this direction ...
87
Electrochemistry Known: Cell Emf … Unknown:
a. Mg(s) + 2H+(aq) ----> Mg+2(aq) + H2(g) E’cell = ? V b. Cu+2(aq) + 2Ag(s) ----> Cu(s) + 2Ag+1(aq) Galvanic? c. 2Zn+2(aq) + 4OH-1(aq) ----> 2Zn(aq) + O2(g) + 2H2O(l) Solution: Split each rx into two ½ rxs … look up cell potentials ... a. reduction: 2H+(aq) + 2e > H2(g) E’ = V oxidation: Mg(s) ----> Mg+2(aq) + 2e-1 E’ = V E’cell = V (Galvanic) b. reduction: Cu+2(aq) + 2e > Cu(s) E’ = V oxidation: 2Ag(s) ----> 2Ag+1(aq) + 2e-1 E’ = V E’cell = V (Not Galvanic) Note: will not run in this direction ... c. Reduction: 2Zn+2(aq) + 4e > 2Zn(s)
88
Electrochemistry Known: Cell Emf … Unknown:
a. Mg(s) + 2H+(aq) ----> Mg+2(aq) + H2(g) E’cell = ? V b. Cu+2(aq) + 2Ag(s) ----> Cu(s) + 2Ag+1(aq) Galvanic? c. 2Zn+2(aq) + 4OH-1(aq) ----> 2Zn(aq) + O2(g) + 2H2O(l) Solution: Split each rx into two ½ rxs … look up cell potentials ... a. reduction: 2H+(aq) + 2e > H2(g) E’ = V oxidation: Mg(s) ----> Mg+2(aq) + 2e-1 E’ = V E’cell = V (Galvanic) b. reduction: Cu+2(aq) + 2e > Cu(s) E’ = V oxidation: 2Ag(s) ----> 2Ag+1(aq) + 2e-1 E’ = V E’cell = V (Not Galvanic) Note: will not run in this direction ... c. Reduction: 2Zn+2(aq) + 4e > 2Zn(s) E’ = V
89
Electrochemistry Known: Cell Emf … Unknown:
a. Mg(s) + 2H+(aq) ----> Mg+2(aq) + H2(g) E’cell = ? V b. Cu+2(aq) + 2Ag(s) ----> Cu(s) + 2Ag+1(aq) Galvanic? c. 2Zn+2(aq) + 4OH-1(aq) ----> 2Zn(aq) + O2(g) + 2H2O(l) Solution: Split each rx into two ½ rxs … look up cell potentials ... a. reduction: 2H+(aq) + 2e > H2(g) E’ = V oxidation: Mg(s) ----> Mg+2(aq) + 2e-1 E’ = V E’cell = V (Galvanic) b. reduction: Cu+2(aq) + 2e > Cu(s) E’ = V oxidation: 2Ag(s) ----> 2Ag+1(aq) + 2e-1 E’ = V E’cell = V (Not Galvanic) Note: will not run in this direction ... c. Reduction: 2Zn+2(aq) + 4e > 2Zn(s) E’ = V Oxidation: 4OH-1(aq) ----> O2(g) + 2H2O(l) + 4e-1
90
Electrochemistry Known: Cell Emf … Unknown:
a. Mg(s) + 2H+(aq) ----> Mg+2(aq) + H2(g) E’cell = ? V b. Cu+2(aq) + 2Ag(s) ----> Cu(s) + 2Ag+1(aq) Galvanic? c. 2Zn+2(aq) + 4OH-1(aq) ----> 2Zn(aq) + O2(g) + 2H2O(l) Solution: Split each rx into two ½ rxs … look up cell potentials ... a. reduction: 2H+(aq) + 2e > H2(g) E’ = V oxidation: Mg(s) ----> Mg+2(aq) + 2e-1 E’ = V E’cell = V (Galvanic) b. reduction: Cu+2(aq) + 2e > Cu(s) E’ = V oxidation: 2Ag(s) ----> 2Ag+1(aq) + 2e-1 E’ = V E’cell = V (Not Galvanic) Note: will not run in this direction ... c. Reduction: 2Zn+2(aq) + 4e > 2Zn(s) E’ = V Oxidation: 4OH-1(aq) ----> O2(g) + 2H2O(l) + 4e-1 E’ = V
91
Electrochemistry Known: Cell Emf … Unknown:
a. Mg(s) + 2H+(aq) ----> Mg+2(aq) + H2(g) E’cell = ? V b. Cu+2(aq) + 2Ag(s) ----> Cu(s) + 2Ag+1(aq) Galvanic? c. 2Zn+2(aq) + 4OH-1(aq) ----> 2Zn(aq) + O2(g) + 2H2O(l) Solution: Split each rx into two ½ rxs … look up cell potentials ... a. reduction: 2H+(aq) + 2e > H2(g) E’ = V oxidation: Mg(s) ----> Mg+2(aq) + 2e-1 E’ = V E’cell = V (Galvanic) b. reduction: Cu+2(aq) + 2e > Cu(s) E’ = V oxidation: 2Ag(s) ----> 2Ag+1(aq) + 2e-1 E’ = V E’cell = V (Not Galvanic) Note: will not run in this direction ... c. Reduction: 2Zn+2(aq) + 4e > 2Zn(s) E’ = V Oxidation: 4OH-1(aq) ----> O2(g) + 2H2O(l) + 4e-1 E’ = V E’cell = V
92
Electrochemistry Known: Cell Emf … Unknown:
a. Mg(s) + 2H+(aq) ----> Mg+2(aq) + H2(g) E’cell = ? V b. Cu+2(aq) + 2Ag(s) ----> Cu(s) + 2Ag+1(aq) Galvanic? c. 2Zn+2(aq) + 4OH-1(aq) ----> 2Zn(aq) + O2(g) + 2H2O(l) Solution: Split each rx into two ½ rxs … look up cell potentials ... a. reduction: 2H+(aq) + 2e > H2(g) E’ = V oxidation: Mg(s) ----> Mg+2(aq) + 2e-1 E’ = V E’cell = V (Galvanic) b. reduction: Cu+2(aq) + 2e > Cu(s) E’ = V oxidation: 2Ag(s) ----> 2Ag+1(aq) + 2e-1 E’ = V E’cell = V (Not Galvanic) Note: will not run in this direction ... c. Reduction: 2Zn+2(aq) + 4e > 2Zn(s) E’ = V Oxidation: 4OH-1(aq) ----> O2(g) + 2H2O(l) + 4e-1 E’ = V E’cell = V (Not Gal)
93
Electrochemistry Key Point …
94
Electrochemistry Key Point … The more positive the E’ Value ...
95
Electrochemistry Key Point …
The more positive the E’ Value ... the more likely the species is to be reduced …
96
Electrochemistry Key Point …
The more positive the E’ Value ... the more likely the species is to be reduced … it is a stronger oxidizing agent ...
97
Electrochemistry Key Point …
The more positive the E’ Value ... the more likely the species is to be reduced … it is a stronger oxidizing agent ... The more negative the E’ Value ...
98
Electrochemistry Key Point …
The more positive the E’ Value ... the more likely the species is to be reduced … it is a stronger oxidizing agent ... The more negative the E’ Value ... the more likely the species is to be oxidized …
99
Electrochemistry Key Point …
The more positive the E’ Value ... the more likely the species is to be reduced … it is a stronger oxidizing agent ... The more negative the E’ Value ... the more likely the species is to be oxidized … it is a stronger reducing agent ...
100
Electrochemistry Key Point …
The more positive the E’ Value ... the more likely the species is to be reduced … it is a stronger oxidizing agent ... The more negative the E’ Value ... the more likely the species is to be oxidized … it is a stronger reducing agent ... Ex: Reduction: Br2(l)+ 2e > 2Br-1(aq) E’ = V
101
Electrochemistry Key Point …
The more positive the E’ Value ... the more likely the species is to be reduced … it is a stronger oxidizing agent ... The more negative the E’ Value ... the more likely the species is to be oxidized … it is a stronger reducing agent ... Ex: Reduction: Br2(l)+ 2e > 2Br-1(aq) E’ = V Oxidation: 2I > I2(l) + 2e-1 E’ = V
102
Electrochemistry Key Point …
The more positive the E’ Value ... the more likely the species is to be reduced … it is a stronger oxidizing agent ... The more negative the E’ Value ... the more likely the species is to be oxidized … it is a stronger reducing agent ... Ex: Reduction: Br2(l)+ 2e > 2Br-1(aq) E’ = V Oxidation: 2I > I2(l) + 2e-1 E’ = V
103
Electrochemistry Key Point …
The more positive the E’ Value ... the more likely the species is to be reduced … it is a stronger oxidizing agent ... The more negative the E’ Value ... the more likely the species is to be oxidized … it is a stronger reducing agent ... Ex: Reduction: Br2(l)+ 2e > 2Br-1(aq) E’ = V Oxidation: 2I > I2(l) + 2e-1 E’ = V E’cell = +.55 V
104
Electrochemistry Known: Reduction Strength
105
Electrochemistry Known: Reduction Strength
Fe+2(aq) + 2e > Fe(s) E’ = V
106
Electrochemistry Known: Reduction Strength
Fe+2(aq) + 2e > Fe(s) E’ = V ClO2(aq) + e > ClO2-1(aq) E’ = V
107
Electrochemistry Known: Reduction Strength
Fe+2(aq) + 2e > Fe(s) E’ = V ClO2(aq) + e > ClO2-1(aq) E’ = V F2(l) + 2e > 2F-1(aq) E’ = V
108
Electrochemistry Known: Reduction Strength
Fe+2(aq) + 2e > Fe(s) E’ = V ClO2(aq) + e > ClO2-1(aq) E’ = V F2(l) + 2e > 2F-1(aq) E’ = V AgCl(s) + e > Ag(s) + Cl-1(aq) E’ = V
109
Electrochemistry Known: Reduction Strength Unknown:
Fe+2(aq) + 2e > Fe(s) E’ = V Rank in order of strength as ClO2(aq) + e > ClO2-1(aq) E’ = V oxidizing agent … F2(l) + 2e > 2F-1(aq) E’ = V AgCl(s) + e > Ag(s) + Cl-1(aq) E’ = V
110
Electrochemistry Known: Reduction Strength Unknown:
Fe+2(aq) + 2e > Fe(s) E’ = V Rank in order of strength as ClO2(aq) + e > ClO2-1(aq) E’ = V oxidizing agent … F2(l) + 2e > 2F-1(aq) E’ = V AgCl(s) + e > Ag(s) + Cl-1(aq) E’ = V Solution: good oxidizing agents are more likely to be in reduced state as they readily strip electrons from other substances …
111
Electrochemistry Known: Reduction Strength Unknown:
Fe+2(aq) + 2e > Fe(s) E’ = V Rank in order of strength as ClO2(aq) + e > ClO2-1(aq) E’ = V oxidizing agent … F2(l) + 2e > 2F-1(aq) E’ = V AgCl(s) + e > Ag(s) + Cl-1(aq) E’ = V Solution: good oxidizing agents are more likely to be in reduced state as they readily strip electrons from other substances … the more positive the E’ value ...
112
Electrochemistry Known: Reduction Strength Unknown:
Fe+2(aq) + 2e > Fe(s) E’ = V Rank in order of increasing ClO2(aq) + e > ClO2-1(aq) E’ = V strength as oxidizing agent … F2(l) + 2e > 2F-1(aq) E’ = V AgCl(s) + e > Ag(s) + Cl-1(aq) E’ = V Solution: good oxidizing agents are more likely to be in reduced state as they readily strip electrons from other substances … the more positive the E’ value ... the more likely a substance will be in reduced form …
113
Electrochemistry Known: Reduction Strength Unknown:
Fe+2(aq) + 2e > Fe(s) E’ = V Rank in order of increasing ClO2(aq) + e > ClO2-1(aq) E’ = V strength as oxidizing agent … F2(l) + 2e > 2F-1(aq) E’ = V AgCl(s) + e > Ag(s) + Cl-1(aq) E’ = V Solution: good oxidizing agents are more likely to be in reduced state as they readily strip electrons from other substances … the more positive the E’ value ... the more likely a substance will be in reduced form … Fe+2 <
114
Electrochemistry Known: Reduction Strength Unknown:
Fe+2(aq) + 2e > Fe(s) E’ = V Rank in order of increasing ClO2(aq) + e > ClO2-1(aq) E’ = V strength as oxidizing agent … F2(l) + 2e > 2F-1(aq) E’ = V AgCl(s) + e > Ag(s) + Cl-1(aq) E’ = V Solution: good oxidizing agents are more likely to be in reduced state as they readily strip electrons from other substances … the more positive the E’ value ... the more likely a substance will be in reduced form … Fe+2 < AgCl <
115
Fe+2 < AgCl < ClO2 <
Electrochemistry Known: Reduction Strength Unknown: Fe+2(aq) + 2e > Fe(s) E’ = V Rank in order of increasing ClO2(aq) + e > ClO2-1(aq) E’ = V strength as oxidizing agent … F2(l) + 2e > 2F-1(aq) E’ = V AgCl(s) + e > Ag(s) + Cl-1(aq) E’ = V Solution: good oxidizing agents are more likely to be in reduced state as they readily strip electrons from other substances … the more positive the E’ value ... the more likely a substance will be in reduced form … Fe+2 < AgCl < ClO2 <
116
Fe+2 < AgCl < ClO2 < F2
Electrochemistry Known: Reduction Strength Unknown: Fe+2(aq) + 2e > Fe(s) E’ = V Rank in order of increasing ClO2(aq) + e > ClO2-1(aq) E’ = V strength as oxidizing agent … F2(l) + 2e > 2F-1(aq) E’ = V AgCl(s) + e > Ag(s) + Cl-1(aq) E’ = V Solution: good oxidizing agents are more likely to be in reduced state as they readily strip electrons from other substances … the more positive the E’ value ... the more likely a substance will be in reduced form … Fe+2 < AgCl < ClO2 < F2
117
Electrochemistry Composing Galvanic Cells …
118
Electrochemistry Composing Galvanic Cells … Known:
a. Ni+2 + 2e > Ni E’ = V
119
Electrochemistry Composing Galvanic Cells … Known:
a. Ni+2 + 2e > Ni E’ = V O2 + 4H+1 + 4e >2H2O E’ = V
120
Electrochemistry Composing Galvanic Cells … Known:
a. Ni+2 + 2e > Ni E’ = V O2 + 4H+1 + 4e >2H2O E’ = V b. Ce+4 + e > Ce+3 E’ = V
121
Electrochemistry Composing Galvanic Cells … Known:
a. Ni+2 + 2e > Ni E’ = V O2 + 4H+1 + 4e >2H2O E’ = V b. Ce+4 + e > Ce+3 E’ = V Sn+2 + 2e > Sn E’ = V
122
Electrochemistry Composing Galvanic Cells … Known: Unknown:
a. Ni+2 + 2e > Ni E’ = V Anode? O2 + 4H+1 + 4e >2H2O E’ = V b. Ce+4 + e > Ce+3 E’ = V Sn+2 + 2e > Sn E’ = V
123
Electrochemistry Composing Galvanic Cells … Known: Unknown:
a. Ni+2 + 2e > Ni E’ = V Anode? O2 + 4H+1 + 4e >2H2O E’ = V Cathode? b. Ce+4 + e > Ce+3 E’ = V Sn+2 + 2e > Sn E’ = V
124
Electrochemistry Composing Galvanic Cells … Known: Unknown:
a. Ni+2 + 2e > Ni E’ = V Anode? O2 + 4H+1 + 4e >2H2O E’ = V Cathode? Balance ... b. Ce+4 + e > Ce+3 E’ = V Sn+2 + 2e > Sn E’ = V
125
Electrochemistry Composing Galvanic Cells … Known: Unknown:
a. Ni+2 + 2e > Ni E’ = V Anode? O2 + 4H+1 + 4e >2H2O E’ = V Cathode? Balance ... b. Ce+4 + e > Ce+3 E’ = V Write Overall Cell Rx ... Sn+2 + 2e > Sn E’ = V
126
Electrochemistry Composing Galvanic Cells … Known: Unknown:
a. Ni+2 + 2e > Ni E’ = V Anode? O2 + 4H+1 + 4e >2H2O E’ = V Cathode? Balance ... b. Ce+4 + e > Ce+3 E’ = V Write Overall Cell Rx ... Sn+2 + 2e > Sn E’ = V Calculate E’cell Solution:
127
Electrochemistry Composing Galvanic Cells … Known: Unknown:
a. Ni+2 + 2e > Ni E’ = V Anode? O2 + 4H+1 + 4e >2H2O E’ = V Cathode? Balance ... b. Ce+4 + e > Ce+3 E’ = V Write Overall Cell Rx ... Sn+2 + 2e > Sn E’ = V Calculate E’cell Solution: Goal ... Which arrangement will make E’cell > 0 ... a. Reversing Ni+2 will create a galvanic cell …
128
Electrochemistry Composing Galvanic Cells … Known: Unknown:
a. Ni+2 + 2e > Ni E’ = V Anode? O2 + 4H+1 + 4e >2H2O E’ = V Cathode? Balance ... b. Ce+4 + e > Ce+3 E’ = V Write Overall Cell Rx ... Sn+2 + 2e > Sn E’ = V Calculate E’cell Solution: Goal ... Which arrangement will make E’cell > 0 ... a. Reversing Ni+2 will create a galvanic cell … Cathode: O2 + 4H+1 + 4e >2H2O E’ = V
129
Electrochemistry Composing Galvanic Cells … Known: Unknown:
a. Ni+2 + 2e > Ni E’ = V Anode? O2 + 4H+1 + 4e >2H2O E’ = V Cathode? Balance ... b. Ce+4 + e > Ce+3 E’ = V Write Overall Cell Rx ... Sn+2 + 2e > Sn E’ = V Calculate E’cell Solution: Goal ... Which arrangement will make E’cell > 0 ... a. Reversing Ni+2 will create a galvanic cell … multiple Ni+2 by 2 ... Cathode: O2 + 4H+1 + 4e >2H2O E’ = V
130
Electrochemistry Composing Galvanic Cells … Known: Unknown:
a. Ni+2 + 2e > Ni E’ = V Anode? O2 + 4H+1 + 4e >2H2O E’ = V Cathode? Balance ... b. Ce+4 + e > Ce+3 E’ = V Write Overall Cell Rx ... Sn+2 + 2e > Sn E’ = V Calculate E’cell Solution: Goal ... Which arrangement will make E’cell > 0 ... a. Reversing Ni+2 will create a galvanic cell … multiple Ni+2 by 2 ... cathode: O2 + 4H+1 + 4e >2H2O E’ = V anode: 2Ni ----> 2Ni+2 + 4e-1 E’ = V
131
Electrochemistry Composing Galvanic Cells … Known: Unknown:
a. Ni+2 + 2e > Ni E’ = V Anode? O2 + 4H+1 + 4e >2H2O E’ = V Cathode? Balance ... b. Ce+4 + e > Ce+3 E’ = V Write Overall Cell Rx ... Sn+2 + 2e > Sn E’ = V Calculate E’cell Solution: Goal ... Which arrangement will make E’cell > 0 ... a. Reversing Ni+2 will create a galvanic cell … multiple Ni+2 by 2 ... cathode: O2 + 4H+1 + 4e >2H2O E’ = V anode: 2Ni ----> 2Ni+2 + 4e-1 E’ = V overall: O2 + 4H+1 + 2Ni ----> 2Ni+2 + 2H2O
132
Electrochemistry Composing Galvanic Cells … Known: Unknown:
a. Ni+2 + 2e > Ni E’ = V Anode? O2 + 4H+1 + 4e >2H2O E’ = V Cathode? Balance ... b. Ce+4 + e > Ce+3 E’ = V Write Overall Cell Rx ... Sn+2 + 2e > Sn E’ = V Calculate E’cell Solution: Goal ... Which arrangement will make E’cell > 0 ... a. Reversing Ni+2 will create a galvanic cell … multiple Ni+2 by 2 ... cathode: O2 + 4H+1 + 4e >2H2O E’ = V anode: 2Ni ----> 2Ni+2 + 4e-1 E’ = V overall: O2 + 4H+1 + 2Ni ----> 2Ni+2 + 2H2O E’cell = V
133
Electrochemistry Composing Galvanic Cells … Known: Unknown:
a. Ni+2 + 2e > Ni E’ = V Anode? O2 + 4H+1 + 4e >2H2O E’ = V Cathode? Balance ... b. Ce+4 + e > Ce+3 E’ = V Write Overall Cell Rx ... Sn+2 + 2e > Sn E’ = V Calculate E’cell Solution: Goal ... Which arrangement will make E’cell > 0 ... b. Reversing Sn+2 reaction will create a galvanic cell …
134
Electrochemistry Composing Galvanic Cells … Known: Unknown:
a. Ni+2 + 2e > Ni E’ = V Anode? O2 + 4H+1 + 4e >2H2O E’ = V Cathode? Balance ... b. Ce+4 + e > Ce+3 E’ = V Write Overall Cell Rx ... Sn+2 + 2e > Sn E’ = V Calculate E’cell Solution: Goal ... Which arrangement will make E’cell > 0 ... b. Reversing Sn+2 reaction will create a galvanic cell … multiply Ce+4 by 2 ... cathode: 2Ce+4 + 2e > 2Ce+3 E’ = V
135
Electrochemistry Composing Galvanic Cells … Known: Unknown:
a. Ni+2 + 2e > Ni E’ = V Anode? O2 + 4H+1 + 4e >2H2O E’ = V Cathode? Balance ... b. Ce+4 + e > Ce+3 E’ = V Write Overall Cell Rx ... Sn+2 + 2e > Sn E’ = V Calculate E’cell Solution: Goal ... Which arrangement will make E’cell > 0 ... b. Reversing Sn+2 reaction will create a galvanic cell … multiply Ce+4 by 2 ... cathode: 2Ce+4 + 2e > 2Ce+3 E’ = V anode: Sn ----> Sn+2 + 2e-1 E’ = V
136
Electrochemistry Composing Galvanic Cells … Known: Unknown:
a. Ni+2 + 2e > Ni E’ = V Anode? O2 + 4H+1 + 4e >2H2O E’ = V Cathode? Balance ... b. Ce+4 + e > Ce+3 E’ = V Write Overall Cell Rx ... Sn+2 + 2e > Sn E’ = V Calculate E’cell Solution: Goal ... Which arrangement will make E’cell > 0 ... b. Reversing Sn+2 reaction will create a galvanic cell … multiply Ce+4 by 2 ... cathode: 2Ce+4 + 2e > 2Ce+3 E’ = V anode: Sn ----> Sn+2 + 2e-1 E’ = V
137
Electrochemistry Composing Galvanic Cells … Known: Unknown:
a. Ni+2 + 2e > Ni E’ = V Anode? O2 + 4H+1 + 4e >2H2O E’ = V Cathode? Balance ... b. Ce+4 + e > Ce+3 E’ = V Write Overall Cell Rx ... Sn+2 + 2e > Sn E’ = V Calculate E’cell Solution: Goal ... Which arrangement will make E’cell > 0 ... b. Reversing Sn+2 reaction will create a galvanic cell … multiply Ce+4 by 2 ... cathode: 2Ce+4 + 2e > 2Ce+3 E’ = V anode: Sn ----> Sn+2 + 2e-1 E’ = V overall rx: 2Ce+4 + Sn ----> Sn+2 + 2Ce+3
138
Electrochemistry Composing Galvanic Cells … Known: Unknown:
a. Ni+2 + 2e > Ni E’ = V Anode? O2 + 4H+1 + 4e >2H2O E’ = V Cathode? Balance ... b. Ce+4 + e > Ce+3 E’ = V Write Overall Cell Rx ... Sn+2 + 2e > Sn E’ = V Calculate E’cell Solution: Goal ... Which arrangement will make E’cell > 0 ... b. Reversing Sn+2 reaction will create a galvanic cell … multiply Ce+4 by 2 ... cathode: 2Ce+4 + 2e > 2Ce+3 E’ = V anode: Sn ----> Sn+2 + 2e-1 E’ = V overall rx: 2Ce+4 + Sn ----> Sn+2 + 2Ce+3 E’cell = V
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Electrochemistry Line Notation ...
140
Electrochemistry Line Notation ... A method of representing electrochemical cells ...
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Electrochemistry Line Notation ... A method of representing electrochemical cells ... shorthand notation used to describe galvanic cells ...
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Electrochemistry Line Notation ... A method of representing electrochemical cells ... shorthand notation used to describe galvanic cells ... The general line notation formation is ...
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anode side || cathode side
Electrochemistry Line Notation ... A method of representing electrochemical cells ... shorthand notation used to describe galvanic cells ... The general line notation formation is ... anode side || cathode side Porous disk or Salt bridge
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anode side || cathode side
Electrochemistry Line Notation ... A method of representing electrochemical cells ... shorthand notation used to describe galvanic cells ... The general line notation formation is ... anode side || cathode side Porous disk or Salt bridge Each side will have a phase boundary separating, e.g., a solid electrode from ions in solution …
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anode side || cathode side
Electrochemistry Line Notation ... A method of representing electrochemical cells ... shorthand notation used to describe galvanic cells ... The general line notation formation is ... anode side || cathode side Porous disk or Salt bridge Each side will have a phase boundary separating, e.g., a solid electrode from ions in solution … such as Cu(s) and Cu+2(aq) ...
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anode side || cathode side
Electrochemistry Line Notation ... A method of representing electrochemical cells ... shorthand notation used to describe galvanic cells ... The general line notation formation is ... anode side || cathode side Porous disk or Salt bridge Each side will have a phase boundary separating, e.g., a solid electrode from ions in solution … such as Cu(s) and Cu+2(aq) ... denoted by a single vertical line (“|”) with the solid phase on the outside …
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Electrochemistry Consider the reaction between copper and zinc ...
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Electrochemistry Consider the reaction between copper and zinc ...
anode: (oxidation) Zn ----> Zn+2 + 2e-1
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Electrochemistry Consider the reaction between copper and zinc ...
anode: (oxidation) Zn ----> Zn+2 + 2e-1 cathode: (reduction) Cu+2 + 2e > Cu
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Electrochemistry Consider the reaction between copper and zinc ...
anode: (oxidation) Zn ----> Zn+2 + 2e-1 cathode: (reduction) Cu+2 + 2e > Cu The line notation is ...
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Zn(s) | Zn+2(aq) || Cu+2(aq) | Cu(s)
Electrochemistry Consider the reaction between copper and zinc ... anode: (oxidation) Zn ----> Zn+2 + 2e-1 cathode: (reduction) Cu+2 + 2e > Cu The line notation is ... Zn(s) | Zn+2(aq) || Cu+2(aq) | Cu(s)
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Zn(s) | Zn+2(aq) || Cu+2(aq) | Cu(s)
Electrochemistry Consider the reaction between copper and zinc ... anode: (oxidation) Zn ----> Zn+2 + 2e-1 cathode: (reduction) Cu+2 + 2e > Cu The line notation is ... Zn(s) | Zn+2(aq) || Cu+2(aq) | Cu(s) Note: On occasion ...
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Zn(s) | Zn+2(aq) || Cu+2(aq) | Cu(s)
Electrochemistry Consider the reaction between copper and zinc ... anode: (oxidation) Zn ----> Zn+2 + 2e-1 cathode: (reduction) Cu+2 + 2e > Cu The line notation is ... Zn(s) | Zn+2(aq) || Cu+2(aq) | Cu(s) Note: On occasion ... only ions (rather than solids) ...
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Zn(s) | Zn+2(aq) || Cu+2(aq) | Cu(s)
Electrochemistry Consider the reaction between copper and zinc ... anode: (oxidation) Zn ----> Zn+2 + 2e-1 cathode: (reduction) Cu+2 + 2e > Cu The line notation is ... Zn(s) | Zn+2(aq) || Cu+2(aq) | Cu(s) Note: On occasion ... only ions (rather than solids) ... Will be involved in the redox process ...
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Zn(s) | Zn+2(aq) || Cu+2(aq) | Cu(s)
Electrochemistry Consider the reaction between copper and zinc ... anode: (oxidation) Zn ----> Zn+2 + 2e-1 cathode: (reduction) Cu+2 + 2e > Cu The line notation is ... Zn(s) | Zn+2(aq) || Cu+2(aq) | Cu(s) Note: On occasion ... only ions (rather than solids) ... Will be involved in the redox process ... in those cases “inert’ ecltrodes are used ...
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Electrochemistry More on line notations …
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Electrochemistry More on line notations … write line notations for the following galvanic cells ...
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Electrochemistry More on line notations … write line notations for the following galvanic cells ...
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Electrochemistry More on line notations … write line notations for the following galvanic cells ... Hg+2 + Cd ----> Hg + Cd+2
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Electrochemistry More on line notations … write line notations for the following galvanic cells ... Hg+2 + Cd ----> Hg + Cd+2 anode: Cd ----> Cd+2 + 2e-1
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Electrochemistry More on line notations … write line notations for the following galvanic cells ... Hg+2 + Cd ----> Hg + Cd+2 anode: Cd ----> Cd+2 + 2e-1 cathode: Hg+2 + 2e > Hg
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Electrochemistry More on line notations … write line notations for the following galvanic cells ... Hg+2 + Cd ----> Hg + Cd+2 anode: Cd ----> Cd+2 + 2e-1 cathode: Hg+2 + 2e > Hg line notation: Cd(s)| Cd+2(aq) || Hg+2(aq) | Hg(s)
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Electrochemistry More on line notations … write line notations for the following galvanic cells ... Hg+2 + Cd ----> Hg + Cd+2 anode: Cd ----> Cd+2 + 2e-1 cathode: Hg+2 + 2e > Hg line notation: Cd(s)| Cd+2(aq) || Hg+2(aq) | Hg(s) Pb + 2Cr > Pb+2 + 2Cr+2
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Electrochemistry More on line notations … write line notations for the following galvanic cells ... Hg+2 + Cd ----> Hg + Cd+2 anode: Cd ----> Cd+2 + 2e-1 cathode: Hg+2 + 2e > Hg line notation: Cd(s)| Cd+2(aq) || Hg+2(aq) | Hg(s) Pb + 2Cr > Pb+2 + 2Cr+2 anode: Pb ----> Pb+2 + 2e-1
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Electrochemistry More on line notations … write line notations for the following galvanic cells ... Hg+2 + Cd ----> Hg + Cd+2 anode: Cd ----> Cd+2 + 2e-1 cathode: Hg+2 + 2e > Hg line notation: Cd(s)| Cd+2(aq) || Hg+2(aq) | Hg(s) Pb + 2Cr > Pb+2 + 2Cr+2 anode: Pb ----> Pb+2 + 2e-1 cathode: 2Cr+3 + 2e > 2 Cr+2
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Electrochemistry More on line notations … write line notations for the following galvanic cells ... Hg+2 + Cd ----> Hg + Cd+2 anode: Cd ----> Cd+2 + 2e-1 cathode: Hg+2 + 2e > Hg line notation: Cd(s)| Cd+2(aq) || Hg+2(aq) | Hg(s) Pb + 2Cr > Pb+2 + 2Cr+2 anode: Pb ----> Pb+2 + 2e-1 cathode: 2Cr+3 + 2e > 2 Cr+2 line notation: Pb(s)| Pb+2(aq) || Cr+3(aq) , Cr+2(aq) | Pt(s)
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Electrochemistry More on line notations … write line notations for the following galvanic cells ... Hg+2 + Cd ----> Hg + Cd+2 anode: Cd ----> Cd+2 + 2e-1 cathode: Hg+2 + 2e > Hg line notation: Cd(s)| Cd+2(aq) || Hg+2(aq) | Hg(s) Pb + 2Cr > Pb+2 + 2Cr+2 anode: Pb ----> Pb+2 + 2e-1 cathode: 2Cr+3 + 2e > 2 Cr+2 line notation: Pb(s)| Pb+2(aq) || Cr+3(aq) , Cr+2(aq) | Pt(s) Cu+2 + 2Pu+4 + 4H2O -----> Cu + 2PuO H+1
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Electrochemistry More on line notations … write line notations for the following galvanic cells ... Hg+2 + Cd ----> Hg + Cd+2 anode: Cd ----> Cd+2 + 2e-1 cathode: Hg+2 + 2e > Hg line notation: Cd(s)| Cd+2(aq) || Hg+2(aq) | Hg(s) Pb + 2Cr > Pb+2 + 2Cr+2 anode: Pb ----> Pb+2 + 2e-1 cathode: 2Cr+3 + 2e > 2 Cr+2 line notation: Pb(s)| Pb+2(aq) || Cr+3(aq) , Cr+2(aq) | Pt(s) Cu+2 + 2Pu+4 + 4H2O -----> Cu + 2PuO H+1 anode: 2Pu+4 + 4H2O ----> 2PuO H+1 + 2e-1
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Electrochemistry More on line notations … write line notations for the following galvanic cells ... Hg+2 + Cd ----> Hg + Cd+2 anode: Cd ----> Cd+2 + 2e-1 cathode: Hg+2 + 2e > Hg line notation: Cd(s)| Cd+2(aq) || Hg+2(aq) | Hg(s) Pb + 2Cr > Pb+2 + 2Cr+2 anode: Pb ----> Pb+2 + 2e-1 cathode: 2Cr+3 + 2e > 2 Cr+2 line notation: Pb(s)| Pb+2(aq) || Cr+3(aq) , Cr+2(aq) | Pt(s) Cu+2 + 2Pu+4 + 4H2O -----> Cu + 2PuO H+1 anode: 2Pu+4 + 4H2O ----> 2PuO H+1 + 2e-1 cathode: Cu+2 + 2e > Cu
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Electrochemistry More on line notations … write line notations for the following galvanic cells ... Hg+2 + Cd ----> Hg + Cd+2 anode: Cd ----> Cd+2 + 2e-1 cathode: Hg+2 + 2e > Hg line notation: Cd(s)| Cd+2(aq) || Hg+2(aq) | Hg(s) Pb + 2Cr > Pb+2 + 2Cr+2 anode: Pb ----> Pb+2 + 2e-1 cathode: 2Cr+3 + 2e > 2 Cr+2 line notation: Pb(s)| Pb+2(aq) || Cr+3(aq) , Cr+2(aq) | Pt(s) Cu+2 + 2Pu+4 + 4H2O -----> Cu + 2PuO H+1 anode: 2Pu+4 + 4H2O ----> 2PuO H+1 + 2e-1 cathode: Cu+2 + 2e > Cu line notation: Pt|Pu+4, PuO2+1, H+1 || Cu+2 | Cu
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Electrochemistry Describing Galvanic Cells …
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Electrochemistry Describing Galvanic Cells …
Cu+2 + 2e > Cu E’ = V
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Electrochemistry Describing Galvanic Cells …
Cu+2 + 2e > Cu E’ = V Cr2O H+1 + 6e > 2Cr+3 + 7H2O E’ = V 1st: E’cell > 0 ...
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Electrochemistry Describing Galvanic Cells …
Cu+2 + 2e > Cu E’ = V Cr2O H+1 + 6e > 2Cr+3 + 7H2O E’ = V 1st: E’cell > 0 ... anode: 3Cu ----> 3Cu+2 + 6e-1 E’ = V
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Electrochemistry Describing Galvanic Cells …
Cu+2 + 2e > Cu E’ = V Cr2O H+1 + 6e > 2Cr+3 + 7H2O E’ = V 1st: E’cell > 0 ... anode: 3Cu ----> 3Cu+2 + 6e-1 E’ = V cathode: Cr2O H+1 + 6e > 2Cr+3 + 7H2O E’ = V
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Electrochemistry Describing Galvanic Cells …
Cu+2 + 2e > Cu E’ = V Cr2O H+1 + 6e > 2Cr+3 + 7H2O E’ = V 1st: E’cell > 0 ... anode: 3Cu ----> 3Cu+2 + 6e E’ = V cathode: Cr2O H+1 + 6e > 2Cr+3 + 7H2O E’ = V overall rx: 3Cu(s) + Cr2O7-2(aq) + 14H+1(aq) ----> 3Cu+2(aq) + 2Cr+3(aq) + 7H2O(l) E’ = V
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Electrochemistry Describing Galvanic Cells …
Cu+2 + 2e > Cu E’ = V Cr2O H+1 + 6e > 2Cr+3 + 7H2O E’ = V 1st: E’cell > 0 ... anode: 3Cu ----> 3Cu+2 + 6e E’ = V cathode: Cr2O H+1 + 6e > 2Cr+3 + 7H2O E’ = V overall rx: 3Cu(s) + Cr2O7-2(aq) + 14H+1(aq) ----> 3Cu+2(aq) + 2Cr+3(aq) + 7H2O(l) E’cell = V Line notation: Cu(s) | Cu+2(aq) || Cr2O7-2(aq) , Cr+3(aq) , H+1(aq) | Pt(s)
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Electrochemistry Describing Galvanic Cells …
Cu+2 + 2e > Cu E’ = V Cr2O H+1 + 6e > 2Cr+3 + 7H2O E’ = V 1st: E’cell > 0 ... anode: 3Cu ----> 3Cu+2 + 6e E’ = V cathode: Cr2O H+1 + 6e > 2Cr+3 + 7H2O E’ = V overall rx: 3Cu(s) + Cr2O7-2(aq) + 14H+1(aq) ----> 3Cu+2(aq) + 2Cr+3(aq) + 7H2O(l) E’cell = V Line notation: Cu(s) | Cu+2(aq) || Cr2O7-2(aq) , Cr+3(aq) , H+1(aq) | Pt(s) Note: Electron flow is from Anode to Cathode, FATCAT, from Copper to Platinum ...
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Electrochemistry Cell Potential, Electrical Work & Free Energy …
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Electrochemistry Cell Potential, Electrical Work & Free Energy …
In general, the actual work that can be achieved is always less than the theoretical work available ...
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Electrochemistry Cell Potential, Electrical Work & Free Energy …
In general, the actual work that can be achieved is always less than the theoretical work available ... The relationship between free energy (maximum is assumed though not attainable) .... And cell potential ... ∆G = -nFE
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Electrochemistry Cell Potential, Electrical Work & Free Energy …
In general, the actual work that can be achieved is always less than the theoretical work available ... The relationship between free energy (maximum is assumed though not atainable) .... And cell potential ... ∆G = -nFE @ standard conditions ...
183
Electrochemistry Cell Potential, Electrical Work & Free Energy …
In general, the actual work that can be achieved is always less than the theoretical work available ... The relationship between free energy (maximum is assumed though not atainable) .... And cell potential ... ∆G = -nFE @ standard conditions ... ∆G’ = -nFE’
184
Electrochemistry Cell Potential, Electrical Work & Free Energy …
In general, the actual work that can be achieved is always less than the theoretical work available ... The relationship between free energy (maximum is assumed though not atainable) .... And cell potential ... ∆G = -nFE @ standard conditions ... ∆G’ = -nFE’ Where ...
185
Electrochemistry Cell Potential, Electrical Work & Free Energy …
In general, the actual work that can be achieved is always less than the theoretical work available ... The relationship between free energy (maximum is assumed though not atainable) .... And cell potential ... ∆G = -nFE @ standard conditions ... ∆G’ = -nFE’ Where ... ∆G = free energy (J)
186
Electrochemistry Cell Potential, Electrical Work & Free Energy …
In general, the actual work that can be achieved is always less than the theoretical work available ... The relationship between free energy (maximum is assumed though not atainable) .... And cell potential ... ∆G = -nFE @ standard conditions ... ∆G’ = -nFE’ Where ... ∆G = free energy (J) n = moles of electrons exchanged in the redox reaction …
187
Electrochemistry Cell Potential, Electrical Work & Free Energy …
In general, the actual work that can be achieved is always less than the theoretical work available ... The relationship between free energy (maximum is assumed though not atainable) .... And cell potential ... ∆G = -nFE @ standard conditions ... ∆G’ = -nFE’ Where ... ∆G = free energy (J) n = moles of electrons exchanged in the redox reaction … F = Faraday, a constant (96,486 Coulombs per mole of electrons)
188
Electrochemistry Cell Potential, Electrical Work & Free Energy …
In general, the actual work that can be achieved is always less than the theoretical work available ... The relationship between free energy (maximum is assumed though not atainable) .... And cell potential ... ∆G = -nFE @ standard conditions ... ∆G’ = -nFE’ Where ... ∆G = free energy (J) n = moles of electrons exchanged in the redox reaction … F = Faraday, a constant (96,486 Coulombs per mole of electrons) E = cell voltage (J/C)
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Electrochemistry Cell Potential, Electrical Work & Free Energy …
In general, the actual work that can be achieved is always less than the theoretical work available ... The relationship between free energy (maximum is assumed though not atainable) .... And cell potential ... ∆G = -nFE @ standard conditions ... ∆G’ = -nFE’ Where ... ∆G = free energy (J) n = moles of electrons exchanged in the redox reaction … F = Faraday, a constant (96,486 Coulombs per mole of electrons) E = cell voltage (J/C) Note: ∆G and E’ have opposite signs... for a spontaneous process ... ∆G is “-” & E’ = “+”
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Electrochemistry Cell Potential, Electrical Work & Free Energy …
Known: Zn+2(aq) + Cu(s) ----> Zn(s) + Cu+2(aq)
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Electrochemistry Cell Potential, Electrical Work & Free Energy …
Known: Unknown: Zn+2(aq) + Cu(s) ----> Zn(s) + Cu+2(aq) ∆G’ = ? KJ
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Electrochemistry Cell Potential, Electrical Work & Free Energy …
Known: Unknown: Zn+2(aq) + Cu(s) ----> Zn(s) + Cu+2(aq) ∆G’ = ? KJ Will Zn ions plate on Cu strip?
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Electrochemistry Cell Potential, Electrical Work & Free Energy …
Known: Unknown: Zn+2(aq) + Cu(s) ----> Zn(s) + Cu+2(aq) ∆G’ = ? KJ Will Zn ions plate on Cu strip? Solution:
194
Electrochemistry Cell Potential, Electrical Work & Free Energy …
Known: Unknown: Zn+2(aq) + Cu(s) ----> Zn(s) + Cu+2(aq) ∆G’ = ? KJ Will Zn ions plate on Cu strip? Solution: 1st: Write the half-reactions ...
195
Electrochemistry Cell Potential, Electrical Work & Free Energy …
Known: Unknown: Zn+2(aq) + Cu(s) ----> Zn(s) + Cu+2(aq) ∆G’ = ? KJ Will Zn ions plate on Cu strip? Solution: 1st: Write the half-reactions ... oxidation rx: Cu(S) ----> Cu+2(aq) + 2e-1 E’ = V reduction rx: Zn+2(aq) + 2e > Zn(s) E’ = V
196
Electrochemistry Cell Potential, Electrical Work & Free Energy …
Known: Unknown: Zn+2(aq) + Cu(s) ----> Zn(s) + Cu+2(aq) ∆G’ = ? KJ Will Zn ions plate on Cu strip? Solution: 1st: Write the half-reactions ... oxidation rx: Cu(S) ----> Cu+2(aq) + 2e-1 E’ = V reduction rx: Zn+2(aq) + 2e > Zn(s) E’ = V E’cell = V
197
Electrochemistry Cell Potential, Electrical Work & Free Energy …
Known: Unknown: Zn+2(aq) + Cu(s) ----> Zn(s) + Cu+2(aq) ∆G’ = ? KJ Will Zn ions plate on Cu strip? Solution: 1st: Write the half-reactions ... oxidation rx: Cu(S) ----> Cu+2(aq) + 2e-1 E’ = V reduction rx: Zn+2(aq) + 2e > Zn(s) E’ = V E’cell = V 2nd: Calculate ∆G’ ....
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Electrochemistry Cell Potential, Electrical Work & Free Energy …
Known: Unknown: Zn+2(aq) + Cu(s) ----> Zn(s) + Cu+2(aq) ∆G’ = ? KJ Will Zn ions plate on Cu strip? Solution: 1st: Write the half-reactions ... oxidation rx: Cu(S) ----> Cu+2(aq) + 2e-1 E’ = V reduction rx: Zn+2(aq) + 2e > Zn(s) E’ = V E’cell = V 2nd: Calculate ∆G’ .... ∆G’ = ? kJ||
199
Electrochemistry Cell Potential, Electrical Work & Free Energy …
Known: Unknown: Zn+2(aq) + Cu(s) ----> Zn(s) + Cu+2(aq) ∆G’ = ? KJ Will Zn ions plate on Cu strip? Solution: 1st: Write the half-reactions ... oxidation rx: Cu(S) ----> Cu+2(aq) + 2e-1 E’ = V reduction rx: Zn+2(aq) + 2e > Zn(s) E’ = V E’cell = V 2nd: Calculate ∆G’ .... ∆G’ = ? kJ|| -nFE’ =
200
Electrochemistry Cell Potential, Electrical Work & Free Energy …
Known: Unknown: Zn+2(aq) + Cu(s) ----> Zn(s) + Cu+2(aq) ∆G’ = ? KJ Will Zn ions plate on Cu strip? Solution: 1st: Write the half-reactions ... oxidation rx: Cu(S) ----> Cu+2(aq) + 2e-1 E’ = V reduction rx: Zn+2(aq) + 2e > Zn(s) E’ = V E’cell = V 2nd: Calculate ∆G’ .... ∆G’ = ? kJ|| -nFE’ = -(2 mole-)(96,486 C/mole-)(-1.10 J/C) =
201
Electrochemistry Cell Potential, Electrical Work & Free Energy …
Known: Unknown: Zn+2(aq) + Cu(s) ----> Zn(s) + Cu+2(aq) ∆G’ = ? KJ Will Zn ions plate on Cu strip? Solution: 1st: Write the half-reactions ... oxidation rx: Cu(S) ----> Cu+2(aq) + 2e-1 E’ = V reduction rx: Zn+2(aq) + 2e > Zn(s) E’ = V E’cell = V 2nd: Calculate ∆G’ .... ∆G’ = ? kJ|| -nFE’ = -(2 mole-)(96,486 C/mole-)(-1.10 J/C) = 2.12 x 105 J
202
Electrochemistry Cell Potential, Electrical Work & Free Energy …
Known: Unknown: Zn+2(aq) + Cu(s) ----> Zn(s) + Cu+2(aq) ∆G’ = ? KJ Will Zn ions plate on Cu strip? Solution: 1st: Write the half-reactions ... oxidation rx: Cu(S) ----> Cu+2(aq) + 2e-1 E’ = V reduction rx: Zn+2(aq) + 2e > Zn(s) E’ = V E’cell = V 2nd: Calculate ∆G’ .... ∆G’ = ? kJ|| -nFE’ = -(2 mole-)(96,486 C/mole-)(-1.10 J/C) = 2.12 x 105 J = 212 kJ
203
Electrochemistry Cell Potential, Electrical Work & Free Energy …
Known: Unknown: Zn+2(aq) + Cu(s) ----> Zn(s) + Cu+2(aq) ∆G’ = ? KJ Will Zn ions plate on Cu strip? Solution: 1st: Write the half-reactions ... oxidation rx: Cu(S) ----> Cu+2(aq) + 2e-1 E’ = V reduction rx: Zn+2(aq) + 2e > Zn(s) E’ = V E’cell = V 2nd: Calculate ∆G’ .... ∆G’ = ? kJ|| -nFE’ = -(2 mole-)(96,486 C/mole-)(-1.10 J/C) = 2.12 x 105 J = 212 kJ Note: Zn+2 ions will not plate out on a Cu(s) at Standard Conditions ...
204
Electrochemistry Cell Potential, Electrical Work & Free Energy …
Known: Unknown: Zn+2(aq) + Cu(s) ----> Zn(s) + Cu+2(aq) ∆G’ = ? KJ Will Zn ions plate on Cu strip? Solution: 1st: Write the half-reactions ... oxidation rx: Cu(S) ----> Cu+2(aq) + 2e-1 E’ = V reduction rx: Zn+2(aq) + 2e > Zn(s) E’ = V E’cell = V 2nd: Calculate ∆G’ .... ∆G’ = ? kJ|| -nFE’ = -(2 mole-)(96,486 C/mole-)(-1.10 J/C) = 2.12 x 105 J = 212 kJ Note: Zn+2 ions will not plate out on a Cu(s) at Standard Conditions ... E’cell < 0
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Electrochemistry Dependence of Cell Potential on Concentration …
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Electrochemistry Dependence of Cell Potential on Concentration …
Concentration Cells ...
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Electrochemistry Dependence of Cell Potential on Concentration …
Concentration Cells ... A cell in which current flows due only to a difference in concentration of an ion in two different compartments of a cell ...
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Electrochemistry Dependence of Cell Potential on Concentration …
Concentration Cells ... A cell in which current flows due only to a difference in concentration of an ion in two different compartments of a cell ... Le Chatelier’s Principle is applicable here ...
209
Electrochemistry Dependence of Cell Potential on Concentration …
Concentration Cells ... A cell in which current flows due only to a difference in concentration of an ion in two different compartments of a cell ... Le Chatelier’s Principle is applicable here ... In a cell where there is an equal concentration of metal ions on both sides ...
210
Electrochemistry Dependence of Cell Potential on Concentration …
Concentration Cells ... A cell in which current flows due only to a difference in concentration of an ion in two different compartments of a cell ... Le Chatelier’s Principle is applicable here ... In a cell where there is an equal concentration of metal ions on both sides ... E’cell = 0 ...
211
Electrochemistry Concentration Cells …
212
Electrochemistry Concentration Cells … Known:
A cell has on its left side a 0.20 M Cu+2 solution ...
213
Electrochemistry Concentration Cells … Known:
A cell has on its left side a 0.20 M Cu+2 solution ... The right side has a M Cu+2 solution ...
214
Electrochemistry Concentration Cells … Known:
A cell has on its left side a 0.20 M Cu+2 solution ... The right side has a M Cu+2 solution ... the compartments are connected by Cu electrodes and a salt bridge ...
215
Electrochemistry Concentration Cells … Known:
A cell has on its left side a 0.20 M Cu+2 solution ... The right side has a M Cu+2 solution ... the compartments are connected by Cu electrodes and a salt bridge ... Unknown:
216
Electrochemistry Concentration Cells … Known:
A cell has on its left side a 0.20 M Cu+2 solution ... The right side has a M Cu+2 solution ... the compartments are connected by Cu electrodes and a salt bridge ... Unknown: Designate the cathode, anode, and direction of current ...
217
Electrochemistry Concentration Cells … Known:
A cell has on its left side a 0.20 M Cu+2 solution ... The right side has a M Cu+2 solution ... the compartments are connected by Cu electrodes and a salt bridge ... Unknown: Designate the cathode, anode, and direction of current ... Solution:
218
Electrochemistry Concentration Cells … Known:
A cell has on its left side a 0.20 M Cu+2 solution ... The right side has a M Cu+2 solution ... the compartments are connected by Cu electrodes and a salt bridge ... Unknown: Designate the cathode, anode, and direction of current ... Solution: Current will flow until the [Cu+2] is equal in both compartments ...
219
Electrochemistry Concentration Cells … Known:
A cell has on its left side a 0.20 M Cu+2 solution ... The right side has a M Cu+2 solution ... the compartments are connected by Cu electrodes and a salt bridge ... Unknown: Designate the cathode, anode, and direction of current ... Solution: Current will flow until the [Cu+2] is equal in both compartments ... this means that the concentration of Cu+2 in the left-hand side (0.20 M) must be reduced by …
220
Electrochemistry Concentration Cells … Known:
A cell has on its left side a 0.20 M Cu+2 solution ... The right side has a M Cu+2 solution ... the compartments are connected by Cu electrodes and a salt bridge ... Unknown: Designate the cathode, anode, and direction of current ... Solution: Current will flow until the [Cu+2] is equal in both compartments ... this means that the concentration of Cu+2 in the left-hand side (0.02 M) must be reduced by … Cu+2 + 2e > Cu
221
Electrochemistry Concentration Cells … Known:
A cell has on its left side a 0.20 M Cu+2 solution ... The right side has a M Cu+2 solution ... the compartments are connected by Cu electrodes and a salt bridge ... Unknown: Designate the cathode, anode, and direction of current ... Solution: Current will flow until the [Cu+2] is equal in both compartments ... this means that the concentration of Cu+2 in the left-hand side (0.02 M) must be reduced by … Cu+2 + 2e > Cu The left-hand side will be the cathode ...
222
Electrochemistry Concentration Cells … Known:
A cell has on its left side a 0.20 M Cu+2 solution ... The right side has a M Cu+2 solution ... the compartments are connected by Cu electrodes and a salt bridge ... Unknown: Designate the cathode, anode, and direction of current ... Solution: Current will flow until the [Cu+2] is equal in both compartments ... this means that the concentration of Cu+2 in the left-hand side (0.02 M) must be reduced by … Cu+2 + 2e > Cu The left-hand side will be the cathode ... the right-hand side (0.050 M Cu+2) will be the anode …
223
Electrochemistry Concentration Cells … Known:
A cell has on its left side a 0.20 M Cu+2 solution ... The right side has a M Cu+2 solution ... the compartments are connected by Cu electrodes and a salt bridge ... Unknown: Designate the cathode, anode, and direction of current ... Solution: Current will flow until the [Cu+2] is equal in both compartments ... this means that the concentration of Cu+2 in the left-hand side (0.02 M) must be reduced by … Cu+2 + 2e > Cu The left-hand side will be the cathode ... the right-hand side (0.050 M Cu+2) will be the anode … current will flow from right to left ...
224
Electrochemistry Concentration Cells … Known:
A cell has on its left side a 0.20 M Cu+2 solution ... The right side has a M Cu+2 solution ... the compartments are connected by Cu electrodes and a salt bridge ... Unknown: Designate the cathode, anode, and direction of current ... Solution: Current will flow until the [Cu+2] is equal in both compartments ... this means that the concentration of Cu+2 in the left-hand side (0.02 M) must be reduced by … Cu+2 + 2e > Cu The left-hand side will be the cathode ... the right-hand side (0.050 M Cu+2) will be the anode … current will flow from right to left ... anode to cathode …
225
Electrochemistry Concentration Cells …
226
Electrochemistry Concentration Cells … produce a very small voltage ...
227
Electrochemistry Concentration Cells … produce a very small voltage ... nonstandard concentrations produce a cell voltage that is different from that at standard concentrations ...
228
Ecell(nonstandard) =/ E’cell
Electrochemistry Concentration Cells … produce a very small voltage ... nonstandard concentrations produce a cell voltage that is different from that at standard concentrations ... Ecell(nonstandard) =/ E’cell
229
Ecell(nonstandard) =/ E’cell
Electrochemistry Concentration Cells … produce a very small voltage ... nonstandard concentrations produce a cell voltage that is different from that at standard concentrations ... Ecell(nonstandard) =/ E’cell Nernst Equation ...
230
Electrochemistry Concentration Cells … produce a very small voltage ... nonstandard concentrations produce a cell voltage that is different from that at standard concentrations ... Ecell(nonstandard) =/ E’cell Nernst Equation ... Ecell = E’cell – (0.0592/n) log Q T = 25 ‘C)
231
Electrochemistry Concentration Cells … produce a very small voltage ... nonstandard concentrations produce a cell voltage that is different from that at standard concentrations ... Ecell(nonstandard) =/ E’cell Nernst Equation ... Ecell = E’cell – (0.0592/n) log Q T = 25 ‘C) Where ... Q = [products]o / [reactants]o
232
Electrochemistry Concentration Cells … produce a very small voltage ... nonstandard concentrations produce a cell voltage that is different from that at standard concentrations ... Ecell(nonstandard) =/ E’cell Nernst Equation ... Ecell = E’cell – (0.0592/n) log Q T = 25 ‘C) Where ... Q = [products]o / [reactants]o If [reactants]o > [products]o ....
233
Electrochemistry Concentration Cells … produce a very small voltage ... nonstandard concentrations produce a cell voltage that is different from that at standard concentrations ... Ecell(nonstandard) =/ E’cell Nernst Equation ... Ecell = E’cell – (0.0592/n) log Q T = 25 ‘C) Where ... Q = [products]o / [reactants]o If [reactants]o > [products]o .... log Q < 0 …
234
Electrochemistry Concentration Cells … produce a very small voltage ... nonstandard concentrations produce a cell voltage that is different from that at standard concentrations ... Ecell(nonstandard) =/ E’cell Nernst Equation ... Ecell = E’cell – (0.0592/n) log Q T = 25 ‘C) Where ... Q = [products]o / [reactants]o If [reactants]o > [products]o .... log Q < 0 … Ecell will be > E’cell ...
235
Electrochemistry Concentration Cells … produce a very small voltage ... nonstandard concentrations produce a cell voltage that is different from that at standard concentrations ... Ecell(nonstandard) =/ E’cell Nernst Equation ... Ecell = E’cell – (0.0592/n) log Q T = 25 ‘C) Where ... Q = [products]o / [reactants]o If [reactants]o > [products]o .... log Q < 0 … Ecell will be > E’cell ... consistent with Le Chatelier’s Principle and concentration cells ….
236
Electrochemistry Concentration Cells … produce a very small voltage ... nonstandard concentrations produce a cell voltage that is different from that at standard concentrations ... Ecell(nonstandard) =/ E’cell Nernst Equation ... Ecell = E’cell – (0.0592/n) log Q T = 25 ‘C) Where ... Q = [products]o / [reactants]o If [reactants]o > [products]o .... log Q < 0 … Ecell will be > E’cell ... consistent with Le Chatelier’s Principle and concentration cells …. When a battery is fully discharged ...
237
Electrochemistry Concentration Cells … produce a very small voltage ... nonstandard concentrations produce a cell voltage that is different from that at standard concentrations ... Ecell(nonstandard) =/ E’cell Nernst Equation ... Ecell = E’cell – (0.0592/n) log Q T = 25 ‘C) Where ... Q = [products]o / [reactants]o If [reactants]o > [products]o .... log Q < 0 … Ecell will be > E’cell ... consistent with Le Chatelier’s Principle and concentration cells …. When a battery is fully discharged ... it is at equilibrium ...
238
Electrochemistry Concentration Cells … produce a very small voltage ... nonstandard concentrations produce a cell voltage that is different from that at standard concentrations ... Ecell(nonstandard) =/ E’cell Nernst Equation ... Ecell = E’cell – (0.0592/n) log Q T = 25 ‘C) Where ... Q = [products]o / [reactants]o If [reactants]o > [products]o .... log Q < 0 … Ecell will be > E’cell ... consistent with Le Chatelier’s Principle and concentration cells …. When a battery is fully discharged ... it is at equilibrium ... Ecell =
239
Electrochemistry Nernst Equation ….
240
Electrochemistry Nernst Equation …. T = 25 ‘C
241
Electrochemistry Nernst Equation …. Known: @ T = 25 ‘C
Cd+2 + 2e > Cd E’ = V
242
Electrochemistry Nernst Equation …. Known: @ T = 25 ‘C
Cd+2 + 2e > Cd E’ = V Pb+2 + 2e > Pb E’ = V
243
Electrochemistry Nernst Equation …. Known: @ T = 25 ‘C
Cd+2 + 2e > Cd E’ = V Pb+2 + 2e > Pb E’ = V [Cd+2] = M
244
Electrochemistry Nernst Equation …. Known: @ T = 25 ‘C
Cd+2 + 2e > Cd E’ = V Pb+2 + 2e > Pb E’ = V [Cd+2] = M [Pb+2] = M
245
Electrochemistry Nernst Equation …. Known: @ T = 25 ‘C Unknown:
Cd+2 + 2e > Cd E’ = V Ecell = ? V Pb+2 + 2e > Pb E’ = V [Cd+2] = M [Pb+2] = M
246
Electrochemistry Nernst Equation …. Known: @ T = 25 ‘C Unknown:
Cd+2 + 2e > Cd E’ = V Ecell = ? V Pb+2 + 2e > Pb E’ = V [Cd+2] = M [Pb+2] = M Solution: 1st: Ecell > 0 V to be Galvanic ...
247
Electrochemistry Nernst Equation …. Known: @ T = 25 ‘C Unknown:
Cd+2 + 2e > Cd E’ = V Ecell = ? V Pb+2 + 2e > Pb E’ = V [Cd+2] = M [Pb+2] = M Solution: 1st: Ecell > 0 V to be Galvanic ... Cd ----> Cd+2 + 2e-1 E’ = V
248
Electrochemistry Nernst Equation …. Known: @ T = 25 ‘C Unknown:
Cd+2 + 2e > Cd E’ = V Ecell = ? V Pb+2 + 2e > Pb E’ = V [Cd+2] = M [Pb+2] = M Solution: 1st: Ecell > 0 V to be Galvanic ... Cd ----> Cd+2 + 2e-1 E’ = V Pb+2 + 2e > Pb E’ = V
249
Electrochemistry Nernst Equation …. Known: @ T = 25 ‘C Unknown:
Cd+2 + 2e > Cd E’ = V Ecell = ? V Pb+2 + 2e > Pb E’ = V [Cd+2] = M [Pb+2] = M Solution: 1st: Ecell > 0 V to be Galvanic ... Cd ----> Cd+2 + 2e-1 E’ = V Pb+2 + 2e > Pb E’ = V Cd(s) + Pb+2(aq) ----> Cd+2(aq) + Pb(s)
250
Electrochemistry Nernst Equation …. Known: @ T = 25 ‘C Unknown:
Cd+2 + 2e > Cd E’ = V Ecell = ? V Pb+2 + 2e > Pb E’ = V [Cd+2] = M [Pb+2] = M Solution: 1st: Ecell > 0 V to be Galvanic ... Cd ----> Cd+2 + 2e-1 E’ = V Pb+2 + 2e > Pb E’ = V Cd(s) + Pb+2(aq) ----> Cd+2(aq) + Pb(s) E’cell = V
251
Electrochemistry Nernst Equation …. Known: @ T = 25 ‘C Unknown:
Cd+2 + 2e > Cd E’ = V Ecell = ? V Pb+2 + 2e > Pb E’ = V [Cd+2] = M [Pb+2] = M Solution: 1st: Ecell > 0 V to be Galvanic ... Cd ----> Cd+2 + 2e-1 E’ = V Pb+2 + 2e > Pb E’ = V Cd(s) + Pb+2(aq) ----> Cd+2(aq) + Pb(s) E’cell = V 2nd: Calculate nonstandard conditions ...
252
Electrochemistry Nernst Equation …. Known: @ T = 25 ‘C Unknown:
Cd+2 + 2e > Cd E’ = V Ecell = ? V Pb+2 + 2e > Pb E’ = V [Cd+2] = M [Pb+2] = M Solution: 1st: Ecell > 0 V to be Galvanic ... Cd ----> Cd+2 + 2e-1 E’ = V Pb+2 + 2e > Pb E’ = V Cd(s) + Pb+2(aq) ----> Cd+2(aq) + Pb(s) E’cell = V 2nd: Calculate nonstandard conditions ... Ecell = ? V||
253
Electrochemistry Nernst Equation …. Known: @ T = 25 ‘C Unknown:
Cd+2 + 2e > Cd E’ = V Ecell = ? V Pb+2 + 2e > Pb E’ = V [Cd+2] = M [Pb+2] = M Solution: 1st: Ecell > 0 V to be Galvanic ... Cd ----> Cd+2 + 2e-1 E’ = V Pb+2 + 2e > Pb E’ = V Cd(s) + Pb+2(aq) ----> Cd+2(aq) + Pb(s) E’cell = V 2nd: Calculate nonstandard conditions ... Ecell = ? V|| E’cell – (0.0592/n) log Q
254
Electrochemistry Nernst Equation …. Known: @ T = 25 ‘C Unknown:
Cd+2 + 2e > Cd E’ = V Ecell = ? V Pb+2 + 2e > Pb E’ = V [Cd+2] = M [Pb+2] = M Solution: 1st: Ecell > 0 V to be Galvanic ... Cd ----> Cd+2 + 2e-1 E’ = V Pb+2 + 2e > Pb E’ = V Cd(s) + Pb+2(aq) ----> Cd+2(aq) + Pb(s) E’cell = V 2nd: Calculate nonstandard conditions ... Ecell = ? V|| E’cell – (0.0592/n) log Q = | E’cell – (0.0592/n) log [[Cd+1]/[Pb+2]] =
255
Electrochemistry Nernst Equation …. Known: @ T = 25 ‘C Unknown:
Cd+2 + 2e > Cd E’ = V Ecell = ? V Pb+2 + 2e > Pb E’ = V [Cd+2] = M [Pb+2] = M Solution: 1st: Ecell > 0 V to be Galvanic ... Cd ----> Cd+2 + 2e-1 E’ = V Pb+2 + 2e > Pb E’ = V Cd(s) + Pb+2(aq) ----> Cd+2(aq) + Pb(s) E’cell = V 2nd: Calculate nonstandard conditions ... Ecell = ? V|| E’cell – (0.0592/n) log Q = | E’cell – (0.0592/n) log [[Cd+1]/[Pb+2]] = = V – (0.0592/2)log [[0.010][0.100]]
256
Electrochemistry Nernst Equation …. Known: @ T = 25 ‘C Unknown:
Cd+2 + 2e > Cd E’ = V Ecell = ? V Pb+2 + 2e > Pb E’ = V [Cd+2] = M [Pb+2] = M Solution: 1st: Ecell > 0 V to be Galvanic ... Cd ----> Cd+2 + 2e-1 E’ = V Pb+2 + 2e > Pb E’ = V Cd(s) + Pb+2(aq) ----> Cd+2(aq) + Pb(s) E’cell = V 2nd: Calculate nonstandard conditions ... Ecell = ? V|| E’cell – (0.0592/n) log Q = | E’cell – (0.0592/n) log [[Cd+1]/[Pb+2]] = = V – (0.0592/2)log [[0.010][0.100]] = – (0.0296) log (0.10) =
257
Electrochemistry Nernst Equation …. Known: @ T = 25 ‘C Unknown:
Cd+2 + 2e > Cd E’ = V Ecell = ? V Pb+2 + 2e > Pb E’ = V [Cd+2] = M [Pb+2] = M Solution: 1st: Ecell > 0 V to be Galvanic ... Cd ----> Cd+2 + 2e-1 E’ = V Pb+2 + 2e > Pb E’ = V Cd(s) + Pb+2(aq) ----> Cd+2(aq) + Pb(s) E’cell = V 2nd: Calculate nonstandard conditions ... Ecell = ? V|| E’cell – (0.0592/n) log Q = | E’cell – (0.0592/n) log [[Cd+1]/[Pb+2]] = = V – (0.0592/2)log [[0.010][0.100]] = – (0.0296) log (0.10) = +0.30V
258
Electrochemistry Nernst Equation …. Known: @ T = 25 ‘C Unknown:
Cd+2 + 2e > Cd E’ = V Ecell = ? V Pb+2 + 2e > Pb E’ = V [Cd+2] = M [Pb+2] = M Solution: 1st: Ecell > 0 V to be Galvanic ... Cd ----> Cd+2 + 2e-1 E’ = V Pb+2 + 2e > Pb E’ = V Cd(s) + Pb+2(aq) ----> Cd+2(aq) + Pb(s) E’cell = V 2nd: Calculate nonstandard conditions ... Ecell = ? V|| E’cell – (0.0592/n) log Q = | E’cell – (0.0592/n) log [[Cd+1]/[Pb+2]] = = V – (0.0592/2)log [[0.010][0.100]] = – (0.0296) log (0.10)
259
Electrochemistry Nernst Equation …. T = 25 ‘C
260
Electrochemistry Nernst Equation …. Known: @ T = 25 ‘C
EQ1: FeO H+1 + 3e > Fe+3 + 4H2O E’ = V
261
Electrochemistry Nernst Equation …. Known: @ T = 25 ‘C
EQ1: FeO H+1 + 3e > Fe+3 + 4H2O E’ = V EQ2: O2+ 4H+1 + 4e > 2 H2O E’ = V
262
Electrochemistry Nernst Equation …. Known: @ T = 25 ‘C
EQ1: FeO H+1 + 3e > Fe+3 + 4H2O E’ = V EQ2: O2+ 4H+1 + 4e > 2 H2O E’ = V [FeO4-2] = 2.0 x 10-3 M
263
Electrochemistry Nernst Equation …. Known: @ T = 25 ‘C
EQ1: FeO H+1 + 3e > Fe+3 + 4H2O E’ = V EQ2: O2+ 4H+1 + 4e > 2 H2O E’ = V [FeO4-2] = 2.0 x 10-3 M [Fe+3] = 1.0 x 10-3 M
264
Electrochemistry Nernst Equation …. Known: @ T = 25 ‘C
EQ1: FeO H+1 + 3e > Fe+3 + 4H2O E’ = V EQ2: O2+ 4H+1 + 4e > 2 H2O E’ = V [FeO4-2] = 2.0 x 10-3 M [O2] = 1.0 x 10-5 atm [Fe+3] = 1.0 x 10-3 M
265
Electrochemistry Nernst Equation …. Known: @ T = 25 ‘C
EQ1: FeO H+1 + 3e > Fe+3 + 4H2O E’ = V EQ2: O2+ 4H+1 + 4e > 2 H2O E’ = V [FeO4-2] = 2.0 x 10-3 M [O2] = 1.0 x 10-5 atm [Fe+3] = 1.0 x 10-3 M pH = 5.2
266
Electrochemistry Nernst Equation …. Known: @ T = 25 ‘C Unknown:
EQ1: FeO H+1 + 3e > Fe+3 + 4H2O E’ = V E’cell = ? V EQ2: O2+ 4H+1 + 4e > 2 H2O E’ = V [FeO4-2] = 2.0 x 10-3 M [O2] = 1.0 x 10-5 atm [Fe+3] = 1.0 x 10-3 M pH = 5.2
267
Electrochemistry Nernst Equation …. Known: @ T = 25 ‘C Unknown:
EQ1: FeO H+1 + 3e > Fe+3 + 4H2O E’ = V E’cell = ? V EQ2: O2+ 4H+1 + 4e > 2 H2O E’ = V [FeO4-2] = 2.0 x 10-3 M [O2] = 1.0 x 10-5 atm [Fe+3] = 1.0 x 10-3 M pH = 5.2 Solution:
268
Electrochemistry Nernst Equation …. Known: @ T = 25 ‘C Unknown:
EQ1: FeO H+1 + 3e > Fe+3 + 4H2O E’ = V E’cell = ? V EQ2: O2+ 4H+1 + 4e > 2 H2O E’ = V [FeO4-2] = 2.0 x 10-3 M [O2] = 1.0 x 10-5 atm [Fe+3] = 1.0 x 10-3 M pH = 5.2 Solution: EQ1 has higher reduction potential ...
269
Electrochemistry Nernst Equation …. Known: @ T = 25 ‘C Unknown:
EQ1: FeO H+1 + 3e > Fe+3 + 4H2O E’ = V E’cell = ? V EQ2: O2+ 4H+1 + 4e > 2 H2O E’ = V [FeO4-2] = 2.0 x 10-3 M [O2] = 1.0 x 10-5 atm [Fe+3] = 1.0 x 10-3 M pH = 5.2 Solution: EQ1 has higher reduction potential ... It wil be reduced ...
270
Electrochemistry Nernst Equation …. Known: @ T = 25 ‘C Unknown:
EQ1: FeO H+1 + 3e > Fe+3 + 4H2O E’ = V E’cell = ? V EQ2: O2+ 4H+1 + 4e > 2 H2O E’ = V [FeO4-2] = 2.0 x 10-3 M [O2] = 1.0 x 10-5 atm [Fe+3] = 1.0 x 10-3 M pH = 5.2 Solution: EQ1 has higher reduction potential ... It wil be reduced ... EQ2 will be oxidized ...
271
Electrochemistry Nernst Equation …. Known: @ T = 25 ‘C Unknown:
EQ1: FeO H+1 + 3e > Fe+3 + 4H2O E’ = V E’cell = ? V EQ2: O2+ 4H+1 + 4e > 2 H2O E’ = V [FeO4-2] = 2.0 x 10-3 M [O2] = 1.0 x 10-5 atm [Fe+3] = 1.0 x 10-3 M pH = 5.2 Solution: EQ1 has higher reduction potential ... It wil be reduced ... EQ2 will be oxidized ... EQ1 is multiplied by 4 ...
272
Electrochemistry Nernst Equation …. Known: @ T = 25 ‘C Unknown:
EQ1: FeO H+1 + 3e > Fe+3 + 4H2O E’ = V E’cell = ? V EQ2: O2+ 4H+1 + 4e > 2 H2O E’ = V [FeO4-2] = 2.0 x 10-3 M [O2] = 1.0 x 10-5 atm [Fe+3] = 1.0 x 10-3 M pH = 5.2 Solution: EQ1 has higher reduction potential ... It wil be reduced ... EQ2 will be oxidized ... EQ1 is multiplied by EQ2 is multiplied by
273
Electrochemistry Nernst Equation …. Known: @ T = 25 ‘C Unknown:
EQ1: FeO H+1 + 3e > Fe+3 + 4H2O E’ = V E’cell = ? V EQ2: O2+ 4H+1 + 4e > 2 H2O E’ = V [FeO4-2] = 2.0 x 10-3 M [O2] = 1.0 x 10-5 atm [Fe+3] = 1.0 x 10-3 M pH = 5.2 Solution: EQ1 has higher reduction potential ... It wil be reduced ... EQ1 will be oxidized ... EQ1 is multiplied by EQ2 is multiplied by 1st: Calculate E’cell .... 4FeO H e > 4Fe H2O E’ = V
274
Electrochemistry Nernst Equation …. Known: @ T = 25 ‘C Unknown:
EQ1: FeO H+1 + 3e > Fe+3 + 4H2O E’ = V E’cell = ? V EQ2: O2+ 4H+1 + 4e > 2 H2O E’ = V [FeO4-2] = 2.0 x 10-3 M [O2] = 1.0 x 10-5 atm [Fe+3] = 1.0 x 10-3 M pH = 5.2 Solution: EQ1 has higher reduction potential ... It wil be reduced ... EQ1 will be oxidized ... EQ1 is multiplied by EQ2 is multiplied by 1st: Calculate E’cell .... 4FeO H e > 4Fe H2O E’ = V 6 H2O ----> 3O2+ 12H e-1 E’ = V
275
Electrochemistry Nernst Equation …. Known: @ T = 25 ‘C Unknown:
EQ1: FeO H+1 + 3e > Fe+3 + 4H2O E’ = V E’cell = ? V EQ2: O2+ 4H+1 + 4e > 2 H2O E’ = V [FeO4-2] = 2.0 x 10-3 M [O2] = 1.0 x 10-5 atm [Fe+3] = 1.0 x 10-3 M pH = 5.2 Solution: EQ1 has higher reduction potential ... It wil be reduced ... EQ1 will be oxidized ... EQ1 is multiplied by EQ2 is multiplied by 1st: Calculate E’cell .... 4FeO H e > 4Fe H2O E’ = V 6 H2O ----> 3O2+ 12H e-1 E’ = V 4FeO4-2(aq) + 20H+1(aq) ----> 4Fe+3 + 3O2(g) + 10H2O(l)
276
Electrochemistry Nernst Equation …. Known: @ T = 25 ‘C Unknown:
EQ1: FeO H+1 + 3e > Fe+3 + 4H2O E’ = V E’cell = ? V EQ2: O2+ 4H+1 + 4e > 2 H2O E’ = V [FeO4-2] = 2.0 x 10-3 M [O2] = 1.0 x 10-5 atm [Fe+3] = 1.0 x 10-3 M pH = 5.2 Solution: EQ1 has higher reduction potential ... It wil be reduced ... EQ1 will be oxidized ... EQ1 is multiplied by EQ2 is multiplied by 1st: Calculate E’cell .... 4FeO H e > 4Fe H2O E’ = V 6 H2O ----> 3O2+ 12H e-1 E’ = V 4FeO4-2(aq) + 20H+1(aq) ----> 4Fe+3 + 3O2(g) + 10H2O(l) E’cell = V
277
Electrochemistry Nernst Equation …. Known: @ T = 25 ‘C Unknown:
EQ1: FeO H+1 + 3e > Fe+3 + 4H2O E’ = V E’cell = ? V EQ2: O2+ 4H+1 + 4e > 2 H2O E’ = V [FeO4-2] = 2.0 x 10-3 M [O2] = 1.0 x 10-5 atm [Fe+3] = 1.0 x 10-3 M pH = 5.2 Solution: EQ1 has higher reduction potential ... It wil be reduced ... EQ1 will be oxidized ... EQ1 is multiplied by EQ2 is multiplied by 1st: Calculate E’cell .... 4FeO H e > 4Fe H2O E’ = V 6 H2O ----> 3O2+ 12H e-1 E’ = V 4FeO4-2(aq) + 20H+1(aq) ----> 4Fe+3 + 3O2(g) + 10H2O(l) E’cell = V 2nd: Calculate the E’cell ...
278
Electrochemistry Nernst Equation …. Known: @ T = 25 ‘C Unknown:
EQ1: FeO H+1 + 3e > Fe+3 + 4H2O E’ = V E’cell = ? V EQ2: O2+ 4H+1 + 4e > 2 H2O E’ = V [FeO4-2] = 2.0 x 10-3 M [O2] = 1.0 x 10-5 atm [Fe+3] = 1.0 x 10-3 M pH = 5.2 Solution: EQ1 has higher reduction potential ... It wil be reduced ... EQ1 will be oxidized ... EQ1 is multiplied by EQ2 is multiplied by 1st: Calculate E’cell .... 4FeO H e > 4Fe H2O E’ = V 6 H2O ----> 3O2+ 12H e-1 E’ = V 4FeO4-2(aq) + 20H+1(aq) ----> 4Fe+3 + 3O2(g) + 10H2O(l) E’cell = V 2nd: Calculate the E’cell ... E = ? V ||
279
Electrochemistry Nernst Equation …. Known: @ T = 25 ‘C Unknown:
EQ1: FeO H+1 + 3e > Fe+3 + 4H2O E’ = V E’cell = ? V EQ2: O2+ 4H+1 + 4e > 2 H2O E’ = V [FeO4-2] = 2.0 x 10-3 M [O2] = 1.0 x 10-5 atm [Fe+3] = 1.0 x 10-3 M pH = 5.2 Solution: EQ1 has higher reduction potential ... It wil be reduced ... EQ1 will be oxidized ... EQ1 is multiplied by EQ2 is multiplied by 1st: Calculate E’cell .... 4FeO H e > 4Fe H2O E’ = V 6 H2O ----> 3O2+ 12H e-1 E’ = V 4FeO4-2(aq) + 20H+1(aq) ----> 4Fe+3 + 3O2(g) + 10H2O(l) E’cell = V 2nd: Calculate the E’cell ... E = ? V || E’cell – (0.059/n) log Q =
280
Electrochemistry Nernst Equation …. Known: @ T = 25 ‘C Unknown:
EQ1: FeO H+1 + 3e > Fe+3 + 4H2O E’ = V E’cell = ? V EQ2: O2+ 4H+1 + 4e > 2 H2O E’ = V [FeO4-2] = 2.0 x 10-3 M [O2] = 1.0 x 10-5 atm [Fe+3] = 1.0 x 10-3 M pH = 5.2 Solution: EQ1 has higher reduction potential ... It wil be reduced ... EQ1 will be oxidized ... EQ1 is multiplied by EQ2 is multiplied by 1st: Calculate E’cell .... 4FeO H e > 4Fe H2O E’ = V 6 H2O ----> 3O2+ 12H e-1 E’ = V 4FeO4-2(aq) + 20H+1(aq) ----> 4Fe+3 + 3O2(g) + 10H2O(l) E’cell = V 2nd: Calculate the E’cell ... E = ? V || E’cell – (0.059/n) log Q = E’cell – (0.059/n) log [[Fe+3]4[O2]3/[FeO4-2]4[H+]20]
281
Electrochemistry Nernst Equation …. Known: @ T = 25 ‘C Unknown:
EQ1: FeO H+1 + 3e > Fe+3 + 4H2O E’ = V E’cell = ? V EQ2: O2+ 4H+1 + 4e > 2 H2O E’ = V [FeO4-2] = 2.0 x 10-3 M [O2] = 1.0 x 10-5 atm [Fe+3] = 1.0 x 10-3 M pH = 5.2 Solution: EQ1 has higher reduction potential ... It wil be reduced ... EQ1 will be oxidized ... EQ1 is multiplied by EQ2 is multiplied by 1st: Calculate E’cell .... 4FeO H e > 4Fe H2O E’ = V 6 H2O ----> 3O2+ 12H e-1 E’ = V 4FeO4-2(aq) + 20H+1(aq) ----> 4Fe+3 + 3O2(g) + 10H2O(l) E’cell = V 2nd: Calculate the E’cell ... E = ? V || E’cell – (0.059/n) log Q = E’cell – (0.059/n) log [[Fe+3]4[O2]3/[FeO4-2][H+]20] = V – (0.059/12) log [[1.0x10-3]4[1.0x10-5]3 /[2.0x10-3]4[6.31x10-6]20
282
Electrochemistry Nernst Equation …. Known: @ T = 25 ‘C Unknown:
EQ1: FeO H+1 + 3e > Fe+3 + 4H2O E’ = V E’cell = ? V EQ2: O2+ 4H+1 + 4e > 2 H2O E’ = V [FeO4-2] = 2.0 x 10-3 M [O2] = 1.0 x 10-5 atm [Fe+3] = 1.0 x 10-3 M pH = 5.2 Solution: EQ1 has higher reduction potential ... It wil be reduced ... EQ1 will be oxidized ... EQ1 is multiplied by EQ2 is multiplied by 1st: Calculate E’cell .... 4FeO H e > 4Fe H2O E’ = V 6 H2O ----> 3O2+ 12H e-1 E’ = V 4FeO4-2(aq) + 20H+1(aq) ----> 4Fe+3 + 3O2(g) + 10H2O(l) E’cell = V 2nd: Calculate the E’cell ... E = ? V || E’cell – (0.059/n) log Q = E’cell – (0.059/n) log [[Fe+3]4[O2]3/[FeO4-2][H+]20] = V – (0.059/12) log [[1.0x10-3]4[1.0x10-5]3 /[2.0x10-3]4[6.31x10-6]20 = V – (4.9 x 10-3) log (6.3 x 1087)
283
Electrochemistry Nernst Equation …. Known: @ T = 25 ‘C Unknown:
EQ1: FeO H+1 + 3e > Fe+3 + 4H2O E’ = V E’cell = ? V EQ2: O2+ 4H+1 + 4e > 2 H2O E’ = V [FeO4-2] = 2.0 x 10-3 M [O2] = 1.0 x 10-5 atm [Fe+3] = 1.0 x 10-3 M pH = 5.2 Solution: EQ1 has higher reduction potential ... It wil be reduced ... EQ1 will be oxidized ... EQ1 is multiplied by EQ2 is multiplied by 1st: Calculate E’cell .... 4FeO H e > 4Fe H2O E’ = V 6 H2O ----> 3O2+ 12H e-1 E’ = V 4FeO4-2(aq) + 20H+1(aq) ----> 4Fe+3 + 3O2(g) + 10H2O(l) E’cell = V 2nd: Calculate the E’cell ... E = ? V || E’cell – (0.059/n) log Q = E’cell – (0.059/n) log [[Fe+3]4[O2]3/[FeO4-2][H+]20] = V – (0.059/12) log [[1.0x10-3]4[1.0x10-5]3 /[2.0x10-3]4[6.31x10-6]20 = V – (4.9 x 10-3) log (6.3 x 1087) = V – 0.43 V =
284
Electrochemistry Nernst Equation …. Known: @ T = 25 ‘C Unknown:
EQ1: FeO H+1 + 3e > Fe+3 + 4H2O E’ = V E’cell = ? V EQ2: O2+ 4H+1 + 4e > 2 H2O E’ = V [FeO4-2] = 2.0 x 10-3 M [O2] = 1.0 x 10-5 atm [Fe+3] = 1.0 x 10-3 M pH = 5.2 Solution: EQ1 has higher reduction potential ... It wil be reduced ... EQ1 will be oxidized ... EQ1 is multiplied by EQ2 is multiplied by 1st: Calculate E’cell .... 4FeO H e > 4Fe H2O E’ = V 6 H2O ----> 3O2+ 12H e-1 E’ = V 4FeO4-2(aq) + 20H+1(aq) ----> 4Fe+3 + 3O2(g) + 10H2O(l) E’cell = V 2nd: Calculate the E’cell ... E = ? V || E’cell – (0.059/n) log Q = E’cell – (0.059/n) log [[Fe+3]4[O2]3/[FeO4-2][H+]20] = V – (0.059/12) log [[1.0x10-3]4[1.0x10-5]3 /[2.0x10-3]4[6.31x10-6]20 = V – (4.9 x 10-3) log (6.3 x 1087) = V – 0.43 V = 0.54 V
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Electrochemistry Nernst Equation ….
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Electrochemistry Nernst Equation Equilibrium ...
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Electrochemistry Nernst Equation Equilibrium ... E & ∆G = Thus ...
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Electrochemistry Nernst Equation Equilibrium ... E & ∆G = Thus ... log K = nE’ / @ 25 ‘C
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Electrochemistry Nernst Equation Equilibrium ... E & ∆G = Thus ... log K = nE’ / @ 25 ‘C
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Electrochemistry Equilibrium Constants and Cell Potential …
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