Name: ________________________________________ Date: __________________ Unit 4 Reactions Write balanced equations from the following word equations: 1. Pure copper can be produced by heating copper (II) sulfide with oxygen. Sulfur dioxide is also produced by this reaction. CuS + O2(g) → Cu(s) + SO2 2. Solid sulfur burns in oxygen gas to form sulfur dioxide. S(s) + O2(g) → SO2 3. A compound manganese (IV) oxide catalyzes the decomposition of an aqueous solution of hydrogen peroxide (H2O2) to produce water and oxygen. 2 H2O2(aq) → 2 H2O(l) + O2(g) 4. Oxygen gas can be made by heating potassium chlorate in the presence of the catalyst manganese (IV) oxide. Potassium chloride is left as a solid residue. 2 KClO3 → 2 KCl(s) + 3 O2(g) 5. When solid mercury (II) sulfide is heated with oxygen, liquid mercury metal and gaseous sulfur dioxide are produced. HgS(s) + O2(g) → Hg(l) + SO2(g)