A carbon compound containing carbon and oxygen has an approximate molar mass of 290. On analysis, it is found to contain 50% by mass of each element. The molecular formula of the compound is:
Correct answer: A. C₁₂O₉
- A. C₁₂O₉
- B. C₄O₃
- C. C₃O₄
- D. C₉O₁₂
Explanation
From the 50% mass data, the empirical formula is found to be C₄O₃ (mass = 96 g/mol). The ratio of molar mass to empirical mass is n = 290/96 ≈ 3. Therefore, the molecular formula is (C₄O₃)₃ or C₁₂O₉.
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