Question

Write balanced chemical equations for action of potassium permanganate on:
(a) Hydrogen
(b) Warm conc. sulphuric acid
Explain why $M{n}^{2+}$ ion is more stable than $M{n}^{3+}$?
(Given: $Mn\to Z=25)$

Answer 1

(a) $2KMn{O}_4+3H_2\to 2Mn{O}_2+2KOH+2H_{2}O$

(b) $6KMn{O}_4+9H_{2}S{O}_4\to 3K_{2}S{O}_4+6MnS{O}_4+9H_{2}O+5O_3$ (The reaction is taking in presence of air)

$M{n}^{2+}$ has half filled $d$ orbital configuration which is more stable the $M{n}^{3+}$ configuration.