Question

1. A constant electric current flows for 3.35 h through electrolytic cells connected in series. One contains a solution of AgNO₃, and the second contains a solution of CuCl₂. During this time, 1.80 g of silver is deposited in the first cell.

(a) How many grams of copper are deposited in the second cell?
g Cu

(b) What is the current flowing in (in amperes) ?
  A

2. Oxalic acid (H₂C₂O₄) is present in many plants and vegetables.

(a) Balance the following equation in acid solution:

MnO₄⁻ + C₂O₄²⁻ →Mn²⁺ + CO₂

→

(b) If a 1.80−g sample of plant matter requires 30.0 mL of 0.0100 M KMnO₄ solution to reach the equivalence point, what is the percent by mass of H₂C₂O₄ in the sample?

3. Balance the following redox equations by the half-reaction method:

(a) Mn²⁺ + H₂O₂

→

MnO₂ + H₂O (in basic solution)

(b) Bi(OH)₃ + SnO₂²⁻

→

SnO₃²⁻ + Bi (in basic solution)

(c) Cr₂O₇²⁻ + C₂O₄²⁻

→

Cr³⁺ + CO₂ (in acidic solution)

(d) ClO₃⁻ + Cl⁻

→

Cl₂ + ClO₂ (in acidic solution)

(e) Mn²⁺ + BiO₃⁻

→

Bi³⁺ + MnO₄⁻ (in acidic solution)

4. iven that E

o

= 0.52 V for the reduction Cu⁺(aq) + e⁻

→

Cu(s), calculate E

o

,

Δ

G

o

, and K for the following reaction at 25

°

C:

2Cu⁺(aq) ⇌ Cu²⁺(aq) + Cu(s)

E o	=	V
Δ G o	=	kJ
K	=	× 10 Enter your answer in scientific notation.

5.Given the following data,

2Hg2+(aq) + 2e− → Hg22+(aq)	E o = 0.92 V
Hg22+(aq) + 2e− → 2Hg(l)	E o = 0.85 V

calculate

Δ

G

o

for the following process at 25

°

C:

Hg22+(aq) → Hg2+(aq) + Hg(l)

kJ / mol

Answer 1