What is the standard emf of a galvanic cell made of a cd electrode in a 1.0 m cd (no3) 2 solution and a cr electrode in a 1.0 m cr (no3) 3 solution at 25°c?

Standard reduction potential of Cd2 + = - 0.403 v

Standard reduction potential of Cr3 + = - 0.74 v

Here, reduction potential of Cd2 + is higher as compared to Cr3+. Hence, it will preferentially undergo reduction.

The electrochemical cell is represented as

Cr/Cr3 + / / Cd2+/Cd

Now, standard EMF of cell = E = ECd2+/Cd - ECr3+/Cr

= - 0.403. - (-0.74)

= 0.337 v