Calculating EoCell and batteries January 9, 2018 Calculating EoCell and batteries Electrochem Learning Target: I CAN calculate Eocell and determine spontaneity of redox reactions

January 9, 2018 Do Now (4 min) Learning Target: I can calculate Eocell and determine spontaneity of redox reactions Do Now: (Complete on your DO NOW SHEET): Balance the following redox reaction via ½ rxn method: ZnCl2 + Au  AuCl + Zn Learning Target: I CAN calculate Eocell and determine spontaneity of redox reactions

Review: Do Now ZnCl2 + Au  AuCl + Zn January 9, 2018 Learning Target: I CAN calculate Eocell and determine spontaneity of redox reactions

announcements Afterschool tutoring – every Wednesday 3 – 4:30 PM January 9, 2018 announcements Afterschool tutoring – every Wednesday 3 – 4:30 PM Final exam: Tuesday and Wednesday, January 16 and 17 PeerGrade: Sign up and log in Homework due Sunday and tuesday Learning Target: I CAN calculate Eocell and determine spontaneity of redox reactions

January 9, 2018 Pogil: Electrochem Take 15 min to independently and silently: Read and Annotate pages 1 - 4 Learning Target: I CAN calculate Eocell and determine spontaneity of redox reactions

Notes: Calculating EoCell for a reaction January 9, 2018 Notes: Calculating EoCell for a reaction Determining standard state cell potentials: A cell's standard state potential is the potential of the cell under standard state conditions, which is approximated with concentrations of 1 mole per liter (1 M) and pressures of 1 atmosphere at 25oC. Eocell Learning Target: I CAN calculate Eocell and determine spontaneity of redox reactions

Notes: Calculating EoCell for a reaction Add Add the potentials of the half-cells to get the overall standard cell potential. Look up Look up the reduction potential for the reverse of the oxidation half-reaction and reverse the sign to obtain the oxidation potential. For the oxidation half-reaction, Eooxidation = -Eoreduction. Look up the reduction potential, Eoreduction, for the reduction half-reaction in a table of reduction potentials Write Write the oxidation and reduction half-reactions for the cell. Notes: Calculating EoCell for a reaction January 9, 2018 Learning Target: I CAN calculate Eocell and determine spontaneity of redox reactions

Calculating EoCell for a reaction January 9, 2018 Calculating EoCell for a reaction Eocell = Eoreduction + Eooxidation Learning Target: I CAN calculate Eocell and determine spontaneity of redox reactions

example: Calculating EoCell for a reaction January 9, 2018 example: Calculating EoCell for a reaction Zn(s) + Cu2+ (aq)  Zn2+ (aq) + Cu(s) Write the half reactions: Zn  Zn2+ + 2e- Cu2+ + 2e-  Cu 2) Look up the standard potentials for the reduction ½ rxn Learning Target: I CAN calculate Eocell and determine spontaneity of redox reactions

example: Calculating EoCell for a reaction January 9, 2018 example: Calculating EoCell for a reaction Zn  Zn2+ + 2e- Cu2+ + 2e-  Cu 3) Look up standard reduction potential for the reverse of ox rxn and change the sign Learning Target: I CAN calculate Eocell and determine spontaneity of redox reactions

example: Calculating EoCell for a reaction January 9, 2018 example: Calculating EoCell for a reaction Zn  Zn2+ + 2e- Cu2+ + 2e-  Cu 4) Add the cell potentials together to get Eocell Learning Target: I CAN calculate Eocell and determine spontaneity of redox reactions

20 min: Work in PAIRS to complete questions 1 - 4 January 9, 2018 Pogil: Electrochem 20 min: Work in PAIRS to complete questions 1 - 4 Learning Target: I CAN calculate Eocell and determine spontaneity of redox reactions

Pogil review Calculating cell potential How to determine spontaneity? January 9, 2018 Pogil review Calculating cell potential How to determine spontaneity? Learning Target: I CAN calculate Eocell and determine spontaneity of redox reactions

January 9, 2018 Exit ticket (3 min) On a separate sheet of paper: What must be the value of Eocell for a redox reaction to be spontaneous? Learning Target: I CAN calculate Eocell and determine spontaneity of redox reactions