Cell Potential Calculation

Question

Calculate the cell potential for the galvanic cell in which the given reaction occurs at 25 °C, given that [Sn²⁺]=0.0624 M, [Fe³⁺]=0.0437 M, [Sn⁴⁺]=0.00655 M, and [Fe²⁺]=0.01139 M. Standard reduction potentials can be found in this table.

Sn²⁺(aq)+2Fe³⁺(aq)↽−−⇀ Sn⁴⁺(aq)+2Fe²⁺(aq)

So far my wrong answers have been:

0.28

0.798

0.178

0.142

0.881

0.61

0.812

Answer 1

to find the cell potential you have to use the nernst equation:

the first step is finding Ecell ^° which is the cell potential at standard conditions, which can be found using the provided table. Ecell^°= reduction potential of reduced -oxidized substance

in this case the Fe is reduced and the Sn is oxidized so using the table we 0.771-0.151=0.62 as the standard cell potential

n=moles of electrons transferred= 2

f= fardays constant =96487 coloumbs/mol

R= ideal gas constant= 8.3145 J/mol K

Ecell= 0.62 - (8.3145)(298)/(2)(96487) ln [(0.00655)(0.01139)²]/(0.0624)(0.0437)^2

Ecell=0.487