1. Catalysts speed up the rate of chemical reactions.   True   False   2. Fill in the missing word: Acid + _______ = Salt + Water   Base   Oxygen   Metal   Non Metal   Hint Half-n-half Clue   3. A pH below 7 indicates _______.   presence of ions   purity of the sample   alkalinity   acidity   Half-n-half Clue   4. A substance that absorbs moisture is called _______.   hygroscopic   hydrophobic   amorphous   hydrophilic   Half-n-half Clue   5. What gas is evolved when dilute sulfuric acid is added to zinc?   Hydrogen Peroxide   Sulfur Dioxide   Hydrogen   Argon   Half-n-half Clue   6. Solubility of a substance in a solvent usually increases with an increase in temperature.   True   False   7. Which of the following is a chemical change?   Dissolving of salt in water   Freezing of water   Boiling of water   Rusting of iron   Half-n-half Clue