78g of a hydrocarbon occupies 22.414 dm3 of volume at S.T.P. The empirical formula of the hydrocarbon is CH. The molecular formula of this hydrocarbon is:
Correct answer: B. C6H6
- A. C2H4
- B. C6H6
- C. C8H8
- D. C4H4
Explanation
Molar mass of CH = 12+1 = 13g Molar mass of the hydrocarbon = 78g as 22.414 dm3 is equal to 1 mol. Molecular formula = n x Empirical formula 78 = n * 13 n = 6 So the molecular formula is 6(CH) = C6H6 i.e. option B.
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