In the laboratory

CHEMISTRY · Single correct · CBSE · Chemistry · d- and f-Block Elements · d- and f-Block Elements

Problem

In the laboratory,

\text{MnO}_2

is made by : (1) heating Mn in

\text{O}_2

(2) oxidising

\text{Mn}^{2+}

in air (3) electrolytic oxidation of

\text{MnSO}_4

(4) precipitating

\text{MnO}_2

from solution when performing titration of

\text{KMnO}_4

in alkaline medium