Q.

In an electrochemical reaction of lead, at standard temperature, if E(Pb2+/Pb)=m Volt and E(Pb4+/Pb)=n Volt, then the value of E(Pb2++Pb4+) is given by m-xn.

The value of x is ______. (Nearest integer)               [2023]


Ans.

(2)

Pb2++2e-Pb                       ΔG10=-2FE10

Pb4++4e-Pb                       ΔG20=-4FE20

Pb2+Pb4++2e-                   ΔG30=-2FE30

ΔG30=ΔG10-ΔG20

-2FE30=-2FE10+4FE20

E30=E10=-2E20

 E30=m-xn

  x=2