1. steam
   1. slowly with water
   2. quickly with steam
   3. iron + steam ---> iron oxide + hydrogen
   4. 3Fe(s) + 4H2O (q) ---> Fe3O4 + 4H2 (g)
2. Hydrogen Chloride
   1. iron + hydrogen chloride --> iron (II) chloride + hydrogen
   2. Fe (s) + 2HCl (g) ---> FeCl2(s) + H2(g)
3. Chlorine
   1. brown fumes
      1. iron (III) chloride
   2. irin + chlorine ----> iron (II) chloride
   3. 2Fe (s) + 3Cl2(g) ---> 2FeCl3(s)
4. Hydroxide formation
   1. iron (II)
      1. iron (II) sulphate + sodium hydroxide ---> iron (II) hydroxide + sodium sulphate
      2. FeSO4 (aq) + 2NaOH (aq) ---> Fe(OH)2 (s) + Na2SO4 (aq)
      3. white when pure
         1. often pale green colour
   2. iron (III)
      1. iron (III) chloride + sodium hydroxide ---> iron(III) hydroxide + sodium chloride
      2. FeCl3(aq) + 3NaOH(aq) ---> Fe(OH)3 (s) + 3NaCl(aq)
      3. orangey-brown colour
   3. depends on iron salt