ChemistryChemical combinationJAMB
A compound contains 80% carbon and 20% hydrogen by mass, and its molar mass is 30 g/mol. Find its molecular formula. [C = 12, H = 1]
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Answer: C. C₂H₆
C : H = 80/12 : 20 = 6.67 : 20 = 1 : 3, so CH₃ (15); 30/15 = 2, giving C₂H₆.
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