Untitled - Kelly Walsh High School

Electrochemistry 279
ANSWER KEY
1. Oxidation is the loss of electrons and reduction is the gain of electrons.
2. a. H 1 and O 2 b. Na 1, S 6, and O 2 c. Fe 3 and Cl 1 d. K 1 and O 1 e. Ca 2, Cr 6, and O 2 3. a. negative b. positive
4. a. cathode b. cathode
5. It is reduced.
6. A faraday is a mole of electrons.
7. a. 2 Cl b. Cr 3 c. 3 e d. 2 e e. 2 e
2 2 3 8. a. Cr2O7 (aq) 14H (aq) 3S (aq) l 2Cr (aq) 3S(s) 7 H2O(l)
2 b. Cl2(g) 2H2O(l) SO2(g) l SO4 (aq) 4H (aq) 2Cl (aq)
c. 5PbO2(s) 4 H (aq) 2 Mn2 (aq) l 5 Pb2 (aq) 2 H2O(l) 2 MnO 4 (aq)
d. 2 Bi3 2 2 (aq) 3 SnO2 (aq) 6 OH (aq) l 3 SnO3 (aq)
3 H2O 2Bi(s)
e. 4 MnO4 (aq) 2 H2O(l) 3 ClO2 (aq) l 4 MnO2(s) 4 OH (aq)
3 ClO 4 (aq)
9. Grams Mg
14.6 g Mg
10. Ecell (0.52 0.15) V 0.37 V
11. E 0.37 V log 0.29 V
12. 2 H2O(l) 2 I (aq) l H2(g) 2 OH a
(aq) I2(s) [1.50]
[0.25] 2b
60 s C 1 mol mol Mg g Mg
(550 min) a ba3.50
1 min s ba ba1 ba24.31
96485 C 2 mol 1 mol Mg
0.0592
1
b