10560 Views

for a cell reaction 2Fe3+ +2I- --------> 2Fe2+ +I2 E=0.24 V at 298K. The standard Gibbs energy of the cell reaction is? (F= 96500 C/mol) a) 23.16kJ/mol. B) -46.32kJ/mol c) -23.16kJ/mol. D) 46.32kJ/mol


Syed Roahan 16th Jan, 2020
Answers (2)
Ayush Mishra 16th Jan, 2020

Hey Syed!

The answer to your question is b) ie -46.32 kj/mol. The solution to the answer can be explained as follows:-

We have E°= 0.24 V

F= 96500 C/mol

and by writing the reduction reactions at two half cells occurring as follows  2Fe3+  +   2e-    =  2 Fe2+

and                                       I2          +2e-     = 2I-

We get the value of n= 2 ( no. of electrons involved in reduction and oxidation of species in two half cells)

Now, we know that Standard Gibbs Free energy, G= -nFE°

PUTTING THE VALUES OBTAINED, G= -2×96500×0.24 ====>  46.32 kj

1 Comment
Comments (1)
16th Jan, 2020
tq
Reply
shivangi mehta 16th Jan, 2020

Hello,

(a) Given:

Reaction: 2Fe 3+ (aq) + 2I (aq) 2Fe 2+ (aq) + I 2 (s)

Standard electrode potential of the cell (E ° cell ) = 0.24V

1 F = 96,500 C mol –1 )

To calculate the standard Gibb’s free energy, we apply the formula given below:

ΔG ° = -nFE ° cell

Where n is the no. of transferred electrons

F is the quantity of electricity flowing,

E ° cell is the standard cell potential

Reduction reaction:

Oxidation reaction:

In the above reactions, the number of electrons transfer(n) = 2e-

ΔG ° = -2× 96,500 × 0.24

ΔG ° = -46320 J/mol

ΔG ° = -46.320 KJ/mol

Thus, the standard Gibbs energy of the cell reaction is (b) -46.32 KJ/mol.

1 Comment
Comments (1)
16th Jan, 2020
tq
Reply
Amity University-Noida B.Tech...
Apply
Among top 100 Universities Globally in the Times Higher Education (THE) Interdisciplinary Science Rankings 2026
VIT - VITEEE 2026
Apply
National level exam conducted by VIT University, Vellore | Ranked #16 by NIRF for Engg. | NAAC A++ Accredited
RV University, Bangalore | La...
Apply
Excellent curriculum; an impressive range of electives, besides core law courses. Up to 100% merit scholarship on a first-come, first-served basis
Amity University-Noida M.Tech...
Apply
Among top 100 Universities Globally in the Times Higher Education (THE) Interdisciplinary Science Rankings 2026
Amity University-Noida MBA Ad...
Apply
Ranked among top 10 B-Schools in India by multiple publications | Top Recruiters-Google, MicKinsey, Amazon, BCG & many more.
Great Lakes Institute of Mana...
Apply
Last Date to Apply: 10th Jan | Globally Recognized by AACSB (US) & AMBA (UK) | 17.8 LPA Avg. CTC for PGPM 2025
View All Application Forms

Download the Careers360 App on your Android phone

Regular exam updates, QnA, Predictors, College Applications & E-books now on your Mobile

150M+ Students
30,000+ Colleges
500+ Exams
1500+ E-books