Question

What is Ecell for the following hypothetical reaction exactly as written (in volts) at T = 25°C given the conditions below? Express your answer to 2 decimal places.

X(s) + Y2+(aq) → X2+(aq) + Y(s)

E°cell = 1.18 V

[Y2+] = 1.39 mol L-1

[X2+] = 0.006 mol L-1

You have 5 attempts at this question.

Answer 1

Nernst Equation:

Ecell = Eccll i ng

Ecell is cell potential

Eocell is standard cell potential

T is temperature in kelvin

n is number of electrons transferred

Faraday's constant ,F=96485 Cmol-1

Gas constant,R=8.314 JK-1mol-1

Q is reaction quotient

lnQ=2.303

Therefore,

Ecell = Ecell – 2.3034 n logo

At 298K (25oC) , the equation will be

0.0592, Ecell = Ecell -- -logQ

Given,Ecell =1.18V ,[Y2+] = 1.39 molL-1 , [X2+] =0.006 molL-1 , n=2

Reaction quotient for the given reaction,

Q = [Y2+1

10.006 1.39

= 4.32 x 10-3

0.0592, Ecell = 1.18 - -log(4.32 x 10-3)

= 1.18 – 0.0592 Ex (-2.36486)

  

= 1.18 - (-0.0699999) V

= 1.2499V

  

= 1.25V