Same chapter4 marksDifficulty: Hard
When 6 g of magnesium is burnt in oxygen, what mass of magnesium oxide is formed? (Mg = 24, O = 16)
Mole Concept and Stoichiometry
4 marksDifficulty: Hard
A compound contains 40% carbon, 6.7% hydrogen and 53.3% oxygen by mass. Find its empirical formula. (C = 12, H = 1, O = 16)
Original Khojo Papers practice question — not from a past board paper.
Answer
CH2O
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
Dividing each percentage by the atomic mass gives 3.33 for carbon, 6.7 for hydrogen and 3.33 for oxygen. Dividing by the smallest, 3.33, gives the ratio 1 : 2 : 1.
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