Question

In which of the following compound manganese shows maximum radius?

• A. $Mn{O}_2$
• B. $KMn{O}_4$
• C. $MnO$
• D. $K_3\left[Mn\right(CN{)}_6]$

Answer 1

The correct option is C $MnO$

Oxidation state of manganese in $Mn{O}_2$ is +4,in $KMn{O}_4$ is +7, in $Mn{O}^{}$ is +2 and in $K_3\left[Mn{\left(CN\right)}_6\right]$ is +3. As oxidation state increases, number of electrons decreases and now nucleas have to pull smaller number of electrons,so radius decreases.So the compound in which manganese has lowest oxidation state has largest radius.

So in $Mn{O}^{}$, manganese shows maximum radius.