Question

Balance the equation:

$Mg+{HNO}_3⟶Mg{\left({NO}_3\right)}_2+N_{2}O+H_{2}O$

Answer 1

$Mg+HN{O}_3\to Mg(N{O}_3{)}_2+N_{2}O+H_{2}O$

$Mg\to M{g}^{2+}+2e$ -(i)

$2HN{O}_3\to N_{2}O+5H_{2}O$ - (ii)

$+8H^{+}+8e^{-}$

$\left(i\right)\times 4+\left(ii\right)$

$4Mg+2HN{O}_3+\to 4M{g}^{2+}+N_{2}O+5H_{2}O$

$+8H^{+}$

Adding $8N{O}_3-$ on both sides

$4Hg+10HN{O}_3\to 4Mg(N{O}_3{)}_2+N_{2}O+5H_{2}O$