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Question
An organic compound, whose vapour density is 45, has the following percentage composition,
H = 2.22%, O = 71.19% and remaining carbon. Calculate its molecular formula.
Solution
The molecular weight of the compound = 90
Empirical formula weight of the compound = 12 + 1 + 2 x 16 = 45
n = `"Molecular weight"/"Empirical formula weight"`
= `90/45`
= 2
∴ Molecular formula of the compound = (CHO2)2
= C2H2O4
= (COOH)2
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