1. Electrolytic Cells
Lab
Lesson 10

2. Electrolytic cell Lab Dec 17, 2008 Full Name
Purpose: To draw and completely analyze five electrolytic cells.
Procedure:
1. Fold a filter paper and place in a watch glass
2. Add 20 mL of electrolyte
3. Immerse the carbon electrodes
in the electrolyte to
complete the electrolytic cell.
Data:

3. 1. KBr(aq) electrolytic cell with phenolphthalein.
Cathode: Anode:
Observations:
Significance:
Power Source e- e- C C - +

4. 1. KBr(aq) electrolytic cell with phenolphthalein. .
Cathode: Anode:
Observations:
Significance:
Power Source e- e- C C - + K+
Br-
H2O

5. 1. KBr(aq) electrolytic cell with phenolphthalein.
Cathode: Anode:
Observations:
Significance:
Power Source e- e- C C - + K+
Br-
H2O

6. 1. KBr(aq) electrolytic cell with phenolphthalein.
Cathode: Anode:
Observations: bubbles
Significance:
Power Source e- e- C C - + K+
Br-
H2O

7. 1. KBr(aq) electrolytic cell with phenolphthalein.
Cathode: Anode:
Observations: bubbles
Significance:
Power Source e- e- C C - + K+
Br-
H2O

8. 1. KBr(aq) electrolytic cell with phenolphthalein.
Cathode: Anode:
Observations: bubbles pink
Significance:
Power Source e- e- C C - + K+
Br-
H2O

9. 1. KBr(aq) electrolytic cell with phenolphthalein.
Cathode: Anode:
Observations: bubbles pink
Significance:
Power Source e- e- C C - + K+
Br-
H2O

10. 1. KBr(aq) electrolytic cell with phenolphthalein.
Cathode: Anode:
Observations: bubbles pink yellow liquid
Significance:
Power Source e- e- C C - + K+
Br-
H2O

11. 1. KBr(aq) electrolytic cell with phenolphthalein.
Cathode: Anode:
Observations: bubbles pink yellow liquid
Significance:
Power Source e- e- C C -
Cathode
Reduction + K+
Br-
H2O

12. 1. KBr(aq) electrolytic cell with phenolphthalein.
Cathode: Anode:
Observations: bubbles pink yellow liquid
Significance:
Power Source e- e- C C -
Cathode
Reduction
2H2O+2e- → H2+ 2OH-
-0.41v + K+
Br-
H2O

13. 1. KBr(aq) electrolytic cell with phenolphthalein.
Cathode: Anode:
Observations: bubbles pink yellow liquid
Significance: H2
Power Source e- e- C C -
Cathode
Reduction
2H2O+2e- → H2+ 2OH-
-0.41 v + K+
Br-
H2O

14. 1. KBr(aq) electrolytic cell with phenolphthalein.
Cathode: Anode:
Observations: bubbles pink yellow liquid
Significance: H2 OH-
Power Source e- e- C C -
Cathode
Reduction
2H2O+2e- → H2+ 2OH-
-0.41 v + K+
Br-
H2O

15. 1. KBr(aq) electrolytic cell with phenolphthalein.
Cathode: Anode:
Observations: bubbles pink yellow liquid
Significance: H2 OH-
Power Source e- e- C C -
Cathode
Reduction
2H2O+2e- → H2+ 2OH-
-0.41 v +
Anode
Oxidation K+
Br-
H2O

16. 1. KBr(aq) electrolytic cell with phenolphthalein.
Cathode: Anode:
Observations: bubbles pink yellow liquid
Significance: H2 OH-
Power Source e- e- C C -
Cathode
Reduction
2H2O+2e- → H2+ 2OH-
-0.41 v +
Anode
Oxidation
2Br- → Br2(l) + 2e-
-1.09 v K+
Br-
H2O

17. 1. KBr(aq) electrolytic cell with phenolphthalein.
Cathode: Anode:
Observations: bubbles pink yellow liquid
Significance: H2 OH- Br2
Power Source e- e- C C -
Cathode
Reduction
2H2O+2e- → H2+ 2OH-
-0.41 v +
Anode
Oxidation
2Br- → Br2(l) + 2e-
-1.09 v K+
Br-
H2O

18. 1. KBr(aq) electrolytic cell with phenolphthalein.
Cathode: Anode:
Observations: bubbles pink yellow liquid
Significance: H2 OH- Br2
Power Source e- e- C C -
Cathode
Reduction
2H2O+2e- → H2+ 2OH-
-0.41 v +
Anode
Oxidation
2Br- → Br2(l) + 2e-
-1.09 v K+
Br-
H2O
2H2O+ 2Br- → H2+ Br2(l) + 2OH- E0 = v MTV = v

19. 2. Na2SO4(aq) electrolytic cell with Yamada’s Indicator.
Cathode: Anode:
Observations: pink bubbles orange bubbles
Significance:
Power Source e- e- C C - +

20. 3. AgNO3(aq) electrolytic cell with Bromocresol Green.
Cathode: Anode:
Observations: white metal yellow bubbles
Significance:
Power Source e- e- C C - +

21. 4. Pb(NO3)2(aq) electrolytic cell with thymol blue.
Cathode: Anode:
Observations: solid metal red bubbles
Significance:
Power Source e- e- C C - +

22. 5. KI(aq) electrolytic cell with phenolphthalein & Starch.
Cathode: Anode:
Observations: pink bubbles black
Significance:
Power Source e- e- C C - +

23. Conclusion State that you did what you set out to do in the purpose.
Define an electrolytic cell.
Do I need to say, do not use pronouns, Navreen?
Start with the main rule and describe how you would completely analyze an electrolytic cell- use your notes, don't be a hero!
Discuss how you determined the anode, cathode, site of oxidation, and site of reduction.
Discuss electron flow and ion migration.
Describe how you determined the anode and cathode reaction and include a discussion of the overpotential effect for water.
Describe what electrolytic cells are used for and list all of the chemicals produced in this lab.