Write chemical equations for the reactions taking place when :
(i) Iron reacts with steam
(ii) Magnesium reacts with dilute HCl
(iii) Copper is heated in air.

Explanation

(i) `{:(3Fe(s) + 4H_(2)O(g) to, Fe_(3)O_(4)(s) + 4H_(2)(g)),(" ""(Steam)", "Fe(II, III)oxide"):}`
(ii) `Mg(s) + 2HCl(aq) to MgCl_(2)(aq) + H_(2)(g)`
(iii) `{:(2Cu(s) + O_(2)(g) overset("heat")to, " "2CuO(s)),(" ""(Air)", "Copper (II) oxide or Cupric oxide"):}`