Question

If the empirical formula of a compound is CH and it has a vapour density of 13, find the molecular formula of the compound.
[C = 12, H = 1]

August 5, 2024

Answer

Empirical formula is CH

Empirical formula weight = 12 + 1 = 13

Vapour density (V.D.) = 13

Molecular weight = 2 × V.D. = 2 × 13 = 26

$Molecular\ weight\over Empirical\ formula\ weight$

$26\over 13 = 2$

∴ Molecular formula = (CH)₂ = C₂H₂

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