Translate the following reactions into balanced chemical equations:
$(i)$ Manganese dioxide is heated with aluminium powder.
$(ii)$ Iron is treated with steam.

(N/A) $(i)$ The reaction between manganese dioxide and aluminium is a thermite reaction: $3 MnO_{2} + 4 Al \longrightarrow 2 Al_{2}O_{3} + 3 Mn$
$(ii)$ The reaction of iron with steam produces iron($II$,$III$) oxide and hydrogen gas: $3 Fe(s) + 4 H_{2}O(g) \longrightarrow Fe_{3}O_{4}(s) + 4 H_{2}(g)$