Question

The standard reduction potential values of three metallic cations $X,Y$ and $Z$ are $0.52,-3.03$ and $-1.18V$ respectively. The order of reducing powers of the corresponding metals is:

• A. $Y>Z>X$
• B. $X>Y>Z$
• C. $Z>Y>X$
• D. $Z>X>Y$

Answer 1

Answer: (A)

$Y>Z>X$

$\to$ Reduction potential value:-

$X\to 0.52V$

$Y\to -3.03V$

$Z\to -1.18V$

$\to$ Positive reduction potential value suggest that reduction reaction involving the addition of electrons is possible. X has positive electrode potential hence, will gain electron & act as oxidizing agent. So, it has least reducing powers among three of them.

$\to$ Negative reduction potential suggest that oxidation involving the loss of electrons is possible. Among $X,Y,Z$, $Y$ has more negative reduction potential hence, will lose electron and act as reducing agent stronger than $Z$.

$\to$ Correct order of reducing power is $Y>Z>X$.