1. KNO3   magnesium oxide   carbon disulfide   sodium chloride   potassium nitrate   Hint Hint       2. NaOH   potassium hydroxide   carbon disulfide   sodium hydroxide   carbon dioxide   Hint       3. H2O   water   sulfuric acid   hydrochloric acid   nitric acid   Hint       4. Na2CO3   sodium carbonate   nitric acid   potassium permanganate   carbon disulfide   Hint       5. CO2   sulfur dioxide   carbon dioxide   sodium hydroxide   hydrogen peroxide   Hint       6. SO2   water   hydrogen peroxide   nitric acid   sulfur dioxide   Hint       7. (NH4)2SO4   hydrogen peroxide   ammonium sulfate   nitric acid   sodium chloride   Hint