Answer
$NO_{2}^{-} (aq) + 2Al (s) + 2H_{2}O (l) → NH_{4}^{+} (aq) + 2AlO_{2}^{-} (aq)$
Oxidizing Agent: $NO_{2}^{-} $
Reducing agent: Al
Work Step by Step
We add water to left side to balance the equation as it is in basic medium. Oxidation state of N is changed from +3 to -3, hence it is reduced and state of Al is changed from 0 to +3, hence it is oxidized.
