Question

Following order is observed in oxidising power of certain ions :
$V{O}_2<C{r}_2{O}^{2-}<Mn{O}_4^{-}$
The reason for this increasing order of oxidising power is

• A. increasing stability of the lower species to which they are reduced
• B. increasing stability of the higher species to which they are oxidised
• C. increasing stability of the higher species to which they are reduced
• D. increasing stability of the lower species to which they are oxidised

Answer 1

Answer: (A)

The given order is : $V{O}_2^{+}<C{r}_2{O}_7^{2-}<Mn{O}_4^{2-}$
The oxidation states of the various transition elements are:
$V-+5;Cr-+6;Mn-+6$
We know that heavier members stabilises higher oxidation state in case of transition elements. So, the given order of oxidising power is based on increasing stability of lower species to which they are reduced.