In an oxidation process,the oxidation number:

In the following reaction,$3CuO + 2NH_3 \to N_2 + 3H_2O + 3Cu$,what happens during the conversion of $NH_3$ to $N_2$?

Observe the following reactions:
$I$. $2H_2O_{(l)} + 2Na_{(s)} \rightarrow 2NaOH_{(aq)} + H_{2(g)}$
$II$. $2H_2O_{(l)} + 2F_{2(g)} \rightarrow 4H^{+}_{(aq)} + 4F^{-}_{(aq)} + O_{2(g)}$
Identify the correct statement from the following:

Which of the following processes occurs during the reaction of $Cu$ with $AgNO_3$ solution?

Which of the following represents the most oxidized form of hydrocarbon?

The conversion of $PbO_2$ to $Pb(NO_3)_2$ is