1. Heat is liberated in   Endothermic Reactions   Substitution Reactions   All chemical reactions   Exothermic Reactions   Hint Half-n-half Clue   2. The lead of a pencil mainly contains   Graphite   Plastics   Lead   Carbon Black   Half-n-half Clue   3. Which of the following is not an acid?   NaOH   H2SO4   HCl   HNO3   Half-n-half Clue   4. Which of the following is a chemical change?   Boiling of water   Rusting of iron   Dissolving of salt in water   Freezing of water   Half-n-half Clue   5. If no more solute can be dissolved in a solvent at a given temperature then that solution is called   An Unstable Solution   A Saturated Solution   A Dispersed Solution   A Real Solution   Half-n-half Clue   6. The two allotropes of phosphorus are   Red Phosphorus, Yellow Phosphorus   Crystalline Phosphorus, Amorphous Phosphorus   Alpha Phosphorus, Beta Phosphorus   Rhombic Phosphorus, Monoclinic Phosphorus   Half-n-half Clue   7. Solubility of a substance in a solvent usually increases with an increase in temperature.   True   False