1. Sodium is very reactive and may burn on exposure to air. Therefore, it is kept under _______.   oil   water   acids   ice   Hint Half-n-half Clue   2. Iron is magnetic in nature.   True   False   3. If a metal's ore is titled 'pyrites', then it most probably contains _______.   sulfur   oxygen   nitrogen   chlorine   Half-n-half Clue   4. Which metal is extracted from the ore 'hematite'?   Manganese   Tin   Aluminum   Iron   Half-n-half Clue   5. An alloy is _______.   an element in the impure form   a solid solution of two or more metals   a compound of three elements   a mixture of three elements   Half-n-half Clue   6. Bronze is an alloy of _______.   lead and copper   barium, zinc and iron   copper and zinc   copper and tin   Half-n-half Clue   7. Which of the following does not belong to this group?   Lead   Sodium   Oxygen   Iron   Half-n-half Clue