Consider the following electrodes P= Zn ²⁺(0.0001 M ) / Zn , Q= Zn ²⁺(0.1 M) / Zn R= Zn ²⁺(0.01 M ) / Zn , S= Zn ²⁺(0.001 M ) / Zn E^ ( Zn / Zn ²⁺ )=-0.76 ~V electrode potentials of the above electrodes in volts are in the order

Step-by-step solution

The standard potential of Zn Zn ²⁺ half-cell =-0.76 ~V Half-cell reaction, Z n ^ 2 * (a q)+ 2 e^ = Z (s)E_ red =E_ red ^ - 0.059 n [ 1 Zn ²⁺ ]=-0.76+ 0.059 n [ Zn ²⁺ ] Lower the concentration of Zn ²⁺ , lower is the E_ red or vice-versa. Hence, the correct order is Q>R>S>P .