Compounds Containing Nitrogen

$\begin{array}{lll}\text { (i) } \mathrm{Br}_2, \mathrm{Fe} & \text { (ii) } \mathrm{Fe}, \mathrm{H}^{+} & \text {(iii) } \mathrm{LiAIH}_4\end{array}$

$\begin{array}{lll}\text { (i) } \mathrm{Br}_2(\mathrm{aq}) & \text { (ii) } \mathrm{LiAIH}_4 & \text { (iii) } \mathrm{H}_3 \mathrm{O}^{+}\end{array}$

(i) $\mathrm{Fe}, \mathrm{H}^{+}$   (ii) $\mathrm{Br}_2$ (aq)   (iii) $\mathrm{HNO}_2$   (iv) $\mathrm{H}_3 \mathrm{PO}_2$

(i) $\mathrm{Fe}, \mathrm{H}^{+}$
  (ii) $\mathrm{Br}_2(\mathrm{aq})$
  (iii) $\mathrm{HNO}_2$
  (iv) $\mathrm{CuBr}$