Question -
Answer -
(i) 2Cr(s) +3Cd2+(aq) → 2Cr3+(aq) + 3Cd
(ii) Fe2+(aq)+ Ag+(aq) → Fe3+(aq) + Ag(s)
Calculatethe ΔrGθ and equilibrium constant of thereactions.
Answer
(i)
The galvanic cell of the givenreaction is depicted as:
Now, the standard cell potentialis
In the given equation,
n = 6
F = 96487 C mol−1
= +0.34 V
Then, 
= −6 × 96487 C mol−1 ×0.34 V= −196833.48 CV mol−1
= −196833.48 J mol−1
= −196.83 kJ mol−1
Again, = −RT ln K = 34.496
K = antilog (34.496)
= 3.13 × 1034
(ii)
The galvanic cell of the givenreaction is depicted as:
Now, the standard cell potentialis
Here, n = 1.
Then,
= −1 × 96487 C mol−1 ×0.03 V
= −2894.61 J mol−1
= −2.89 kJ mol−1
Again, 
= 0.5073
K = antilog (0.5073)
= 3.2 (approximately)