Write short notes on:

(i) Isomerization reactions.
(ii) Balanced equations.

Classify the following reaction according to its nature: 

$2{\mathrm{H}}_2+{\mathrm{O}}_2\to 2{\mathrm{H}}_2\mathrm{O}$

Classify the following reaction according to its nature: (Isomerization reaction/ Decomposition reaction)

${\mathrm{NH}}_4\mathrm{CNO}\to {\mathrm{H}}_2{\mathrm{NCONH}}_2$

Classify the following reaction according to its nature:

${\mathrm{NH}}_3+{\mathrm{H}}_2\mathrm{O}\to {\mathrm{NH}}_4\mathrm{OH}$