Question

The standard (reduction) electrode potentials for metal-metal ion $(M/M^{2+})$ electrodes $P, Q, R$ and $S$ are respectively $-0.44 \, V, +0.34\, V, -0.76\,V$ and $-0.25 \, V$ The increasing order of their reducing capacities is

• A. $ P
• B. $ Q
• C. $ Q < ,S
• D. $ P

Answer 1

Answer: (B)

$ Q

Answer 2

More negative the reduction potential of a metal, higher is its reducing capacity. Therefore, the increasing order of reduction capacities is
$\begin{matrix}Q&