electrochem. Consider the following reaction at 298K. Co2+ (aq) + 2 Ag (s) Co (s) + 2 Ag+ (aq) ?

The two half reactions and their Eo values are:
Co2+(aq) + 2e- --> Co(s) Eo = -0.28 V
Ag(s) --> Ag+(aq) + e- Eo = -0.80 V

Ecell = -1.08 V

So there are a couple of equations to think about to get to the answers for this question:

Delta Go = - n F Eo and
Delta Go = -RT ln K

Looking at the first, if Eo is negative, then Delta Go will be positive. Likewise, looking at the second, if Delta G>0, K<1. So,

1. Eocell < 0 THIS IS TRUE

2. n = 3 mol electrons THIS IS FALSE. n = 2 mol electrons

3. The reaction is product-favored. THIS IS FALSE.

4. K < 1 THIS IS TRUE.

5. delta Go < 0 THIS IS FALSE

1. True
Since Ag is less reactive than Co, the reaction is not spontaneous. Hence, E°(cell) < 0

2. False
Reducing half equation: Co²⁺(aq) + 2e⁻ → Co(s)
Oxidation half equation: 2Ag(s) → 2Ag⁺(aq) + 2e⁻
Hence, n = 3

3. False
Since the reaction is not spontaneous, it is reactant-favored.

4. True
E°(cell) = (RT/nF) ln(K)
Since E°(cell) < 0, K < 1

5. False
The reaction is not spontaneous. Hence, ΔG° > 0

The answers: 1 and 4