1. A substance that speeds up the rate of a chemical reaction without undergoing any change itself is known as a _______.   cation   catalyst   nucleus   counter ion   Hint Half-n-half Clue   2. The two allotropes of phosphorus are _______ and _______.   Red, Yellow   Rhombic, Monoclinic   Alpha, Beta   Crystalline, Amorphous   Half-n-half Clue   3. Catalysts speed up the rate of chemical reactions.   True   False   4. A pH below 7 indicates _______.   alkalinity   acidity   purity of the sample   presence of ions   Half-n-half Clue   5. Lemon juice is _______ in nature.   metallic   acidic   neutral   basic   Half-n-half Clue   6. A substance that absorbs moisture is called _______.   hygroscopic   hydrophobic   amorphous   hydrophilic   Half-n-half Clue   7. What gas is evolved when dilute sulfuric acid is added to zinc?   Hydrogen   Argon   Hydrogen Peroxide   Sulfur Dioxide   Half-n-half Clue