1. What is the combination of any substance with oxygen known as?   Reduction   Hydrogenation   Oxidation   Combustion   Hint Half-n-half Clue   2. Catalysts often speed up certain chemical reactions.   False   True   3. A pH of below 7 indicates   Presence of Ions   Acidity   Purity of the sample   Alkalinity   Half-n-half Clue   4. Lemon juice is   Metallic   Basic   Neutral   Acidic   Half-n-half Clue   5. Fizziness in Coco-Cola/Pepsi is caused by   Carbon Dioxide   Hydrogen   Helium   Nitrogen   Half-n-half Clue   6. Which of the following is not a physical change?   Oxidation   Decantation   Distillation   Precipitation   Half-n-half Clue   7. If no more solute can be dissolved in a solvent at a given temperature then that solution is called   A Saturated Solution   A Dispersed Solution   A Real Solution   An Unstable Solution   Half-n-half Clue