1. Fill in the missing word: _______ + oxygen = Magnesium oxide   carbon   manganese   metal   magnesium   Hint Half-n-half Clue   2. Metals that can be easily drawn into wires are known as _______ metals.   malleable   stretchable   ductile   polymer   Half-n-half Clue   3. Rocks that are rich in metals are known as _______.   allotropes   ores   metalloids   slag   Half-n-half Clue   4. Which of the following metals is often found in the pure state?   Iron   Magnesium   Aluminum   Gold   Half-n-half Clue   5. With which metal does oxygen combine to form rust?   Silver   Iron   Platinum   Gold   Half-n-half Clue   6. Which metal is extracted from the ore 'hematite'?   Iron   Tin   Manganese   Aluminum   Half-n-half Clue   7. Rust on iron is basically _______.   a sulphide   an oxide   a nitride   a chloride   Half-n-half Clue