Electrolysis.  Running a galvanic cell backwards.  Put a voltage bigger than the cell potential on the wire and reverse the direction of the redox reaction.

Slides:



Advertisements
Similar presentations
Electrochemistry Applications of Redox.
Advertisements

Electrochemistry.
PART 2: Electrochemistry Unit 09: Oxidation and Reduction.
Electrochemical & Voltaic Cells
Created by C. Ippolito March 2007 Updated March 2007 Chapter 22 Electrochemistry Objectives: 1.describe how an electrolytic cell works 2.describe how galvanic.
Electrolysis & Understanding Electrolytic Cells : When a non-spontaneous redox reaction is made to occur by putting electrical energy into the system.
Cells and Voltage.
19.2 Galvanic Cells 19.3 Standard Reduction Potentials 19.4 Spontaneity of Redox Reactions 19.5 The Effect of Concentration on Emf 19.8 Electrolysis Chapter.
Electrochemistry Two broad areas Galvanic Rechargeable Electrolysys Cells batteries Cells.
Electrochemistry The first of the BIG FOUR. Introduction of Terms  Electrochemistry- using chemical changes to produce an electric current or using electric.
Electrochemistry. 17.1/17.2 GALVANIC CELLS AND STANDARD REDUCTION POTENTIALS Day 1.
Electrochemistry Chapter 19.
The End is in Site! Nernst and Electrolysis. Electrochemistry.
ELECTROCHEMICAL CELLS. TASK Sequence these elements starting from the most reactive to the least reactive: Na, Pt, Au, C, H, Sn, Pb, Al, C, Mg, Li, Ca,
Applications of Redox Your last chapter! I know, …… kinda sad.
Electrolysis. Drill What is the color of the following ion in solution? Nickel Ans: green Copper Ans: blue Cobalt Ans: pink Iron (II) Ans: light blue.
“minimal” galvanic cells
Electrochemistry Applications of Redox. Review l Oxidation reduction reactions involve a transfer of electrons. l OIL- RIG l Oxidation Involves Loss l.
Electrochemistry. Electrochemical Cells  Electrons are transferred between the particles being oxidized and reduced  Two types –Spontaneous = Voltaic.
Electrochemistry Applications of Redox. Review  Oxidation reduction reactions involve a transfer of electrons.  OIL- RIG  Oxidation Involves Loss 
 17.1 Explain how a non-spontaneous redox reaction can be driven forward during electrolysis  17.1 Relate the movement of charge through an electrolytic.
Electrochemistry. Table of Reduction Potentials Measured against the Standard Hydrogen Electrode.
Electrochemistry Guaranteed to give you a jolt. Electrochemical cells  A chemical system in which oxidation and reduction can occur – often a single.
1 Electrolytic Cells Voltaic cells are spontaneous with E > 0. What’s going on in a voltaic cell? A voltaic cell converts chemical energy into electrical.
Electrochemistry The study of the interchange of chemical and electrical energy.
Electrochemical cell. Parts of a Voltaic Cell The electrochemical cell is actually composed to two half cells. Each half cell consists of one conducting.
Electrochemistry Mr. Weldon. 1. Definition: Field that deals with chemical changes caused by electric current and the production of electricity by chemical.
Chapter 17 Electrochemistry Study Of Interchange Of Chemical And Electrical Energy Using RedOx chemistry to generate an electrical current – moving electrons.
Electrolysis Chapter 17 Section 7 Electrochemistry e-
Electrochemistry Electrolysis.
REDOX Part 2 - Electrochemistry Text Ch. 9 and 10.
Electrolysis. In a galvanic cell, a redox reaction occurs to produce electricity. In an electrolytic cell, electricity is used to produce a redox reaction.
Electrolysis Electrolysis: Forcing a current through a cell to produce a chemical change for which the cell potential is negative. A Galvanic Cell in Reverse!!!
Batteries Electrochemical cells  Terms to know Anode Cathode Oxidation Reduction Salt Bridge Half cell Cell potential Electron flow Voltage.
Galvanic Cells ELECTROCHEMISTRY/CHEMICAL REACTIONS SCH4C/SCH3U.
Chapter 19 Last Unit Electrochemistry: Voltaic Cells and Reduction Potentials.
Electrolytic Cells Chemistry Chapter 19 E.
18.8 Electrolysis: Driving Non-Spontaneous Chemical Reactions with Electricity.
Electrochemistry Hope you get a charge out of this one!!!!
Topic 19 Oxidation and Reduction. 1)What is the oxidation number of P in PO 4 -3 ? 2)If Cu and Zn and connected, which is the anode? 3)What reaction (oxidation.
mr4iE. batteries containers of chemicals waiting to be converted to electricity the chemical reaction does not.
Electrolysis 3.7 Electrolysis…. Electrolysis Use of electrical energy to produce chemical change...forcing a current through a cell to produce a chemical.
Electrochemistry.
Chapter 10.7 Electrolysis.
Electrolytic Cells galvanic cell electrolytic cell 2 H2(g) + O2(g) 
Ch. 20: Electrochemistry Lecture 4: Electrolytic Cells & Faraday’s Law.
H.W. # 24 Study pp (sec ) Ans. ques. p. 883 # 93a,95c,97,104,105,
Electrochemistry RedOx: Part Deux.
“minimal” galvanic cells
Electrochemistry Applications of Redox.
Electrochemistry the study of the interchange of chemical and electrical energy.
Chapter 19 Electrochemistry Semester 1/2009 Ref: 19.2 Galvanic Cells
“minimal” galvanic cells
Electrochemistry RedOx: Part Deux.
Electrolytic Cells Aim: Write half reactions for electrolysis of a salt and electroplating.
Electrochemistry.
Harnessing the changes in oxidation and reduction
10.2 Electrochemistry Objectives S2
Electrochemistry.
Electrochemistry.
Electrolytic Cells galvanic cell electrolytic cell 2 H2(g) + O2(g) 
Electrochemistry.
Stoichiometry of Cells
Electrochemistry Applications of Redox.
You will have to completely label a diagram to look like this
Aim # 36: What is the difference between a
Electrochemistry Lesson 3
Work Work is never the maximum possible if any current is flowing.
Electrochemistry.
Ch. 17 Electrochemistry.
Presentation transcript:

Electrolysis

 Running a galvanic cell backwards.  Put a voltage bigger than the cell potential on the wire and reverse the direction of the redox reaction.  The Cathode & Anode swap as well as the flow direction of the ions.  Used for electroplating. Electrolysis

1.0 M Zn +2 e-e- e-e- Anode Cathode 1.10 Zn Cu 1.0 M Cu +2

1.0 M Zn +2 e-e- e-e- Anode Cathode A battery >1.10V Zn Cu 1.0 M Cu +2

Draw the following cell….  2I - (ag) + Cu 2+ (ag)  I 2(s) + Cu (s)  Which process takes place at the anode? Cathode?  What are the electrodes made of?  What is the direction of electron flow? Is the reaction spontaneous?  What Voltage is necessary to force electrolysis?

Electroplating  Place a current on the system which is greater then the potential at which the metal ion is reduced.  The metal will plate out.  The amount of metal reduced is directly related to the current in Amps. Amps = Coulombs/sec  Not a perfectly efficient process.

Calculating plating  Use Stoichiometry to solve.  G  moles  moles of e-  coulombs  Current  time  How long must 6.00 amp current be applied to produce 15.5 g of Au from Au 3+ ?

Another Approach  An aqueous solution of Lead II chloride contains 927g of lead chloride. What current (in Amps) is necessary to remove all the lead from the solution in 48 hours?

Other uses  Electrolysis of water.  Separating mixtures of ions.  More positive reduction potential means the reaction proceeds forward forming products.  These need less current to reduce.  Most positive reduction potential is easiest to plate out of solution.

Predict the order of reduction for the following ions…  Ag +, Zn 2+, IO 3 -  Ag + + e-  Ag  Zn e-  Zn  IO H + + 5e -  ½ I 2 + 3H 2 O