A hydrogen gas electrode is made by dipping platinum wire in a solution of HCl of pH = 10 and by passing hydrogen gas around the platinum wire at one atm pressure, The oxidation potential of electrode would be

1- 0.59V 2- 0.118V

3- 1.18V 4- 0.059V

Ans is - 0.59 V

As pH = 10

and pH = - log[H+]

      10 = - log[H+]

 [H+] = 10-10

Now according to Nernst equation,

Ecell​ = Eocell - 2.303 RTnFlog[H2][H+]

Half cell reaction is 

H+(aq)  +   e-  12H2 (g)

Thus n = 1 and RTF= 0.0591

Now for this reaction E0cell = 0 V

So   Ecell = 0 - 0.0591 log(1/10-10)

              = - 0.0591 log 1010

 ​= - 0.0591 x 10
 ​Ecell = - 0.591 V
The correct option is (1).
 

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