1. CaCO3   carbon disulfide   carbon dioxide   calcium carbonate   sulfuric acid   Hint Hint       2. KMnO4   nitric acid   sodium chloride   potassium permanganate   hydrogen peroxide   Hint       3. KNO3   ammonium sulfate   sodium carbonate   potassium nitrate   calcium carbonate   Hint       4. H2O2   potassium hydroxide   hydrogen peroxide   magnesium oxide   water   Hint       5. H2O   sodium chloride   copper sulfate   water   potassium permanganate   Hint       6. MgO   sodium carbonate   magnesium oxide   copper sulfate   carbon disulfide   Hint       7. CS2   carbon disulfide   carbon dioxide   sodium hydroxide   sulfur dioxide   Hint