isolation of Group 8B(10) elements, used as industrial catalysts, involves a series of steps. For nickel, the sulfide ore is roasted in air:Ni₃S₂(s) + O₂(g) ⇄ NiO(s) + SO₂(g) .The metal oxide is reduced by the H₂ in water gas (CO + H₂) to impure Ni: NiO(s) + H₂(g) ⇄ Ni(s) + H₂O The CO in water gasthen reacts with the metal in the Mond process to form gaseous nickel carbonyl, Ni(s) + CO(g) ⇄ Ni(CO)₄(g) which is subsequently decomposed to the metal. (a) Balance each of the three steps, and obtain an overall balanced equation for the conversion of Ni₃S₂ to Ni(CO)₄.