Question

In which of the following compound $Mn$ shows minimum radius?

• A. $Mn{O}_2$
• B. $KMn{O}_4$
• C. $MnO$
• D. None of these

Answer 1

Answer: (B)

$KMn{O}_4$

As oxidation state of central metal ion increases, the electron to proton ratio decreases and therefore, size of ion decreases. In $KMn{O}_4$, $Mn$ is in +7 oxidation sate. So, due to maximum +ve charge radius will be lowest.