Same chapter4 marksDifficulty: Hard
When 6 g of magnesium is burnt in oxygen, what mass of magnesium oxide is formed? (Mg = 24, O = 16)
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4 marksDifficulty: Hard
Calculate the mass of calcium oxide obtained by heating 100 g of pure calcium carbonate. (Ca = 40, C = 12, O = 16)
Original Khojo Papers practice question — not from a past board paper.
Answer
56 g
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
CaCO3 → CaO + CO2. The molar masses are 100 g and 56 g, so 100 g of the carbonate gives 56 g of the oxide.
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