Solution: 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 + H ₂) to impure Ni: NiO(s) + H₂(g) ⇌ Ni(s) + H₂O(g). The CO in water gas then 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.