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Question
The Empirical formula of an organic compound is CHCl2.
If its relative molecular mass is 168, what is its molecular formula?
[At. Wt. C = 12, H = 1, Cl = 35.5]
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Solution
Empirical formula of organic compound = CHCl2
Molecular Mass (M.M.) = 168
Empirical formula mass
= [12 × 1 + 1 × 1 + 35.5 × 2]
= 12 + 1 + 71
= 84
n = `"Molecular Mass"/"Empirical Formula Mass"`
= `168/84`
Molecular Formula = n × Empirical formula
= 2 × CHCl2
= C2H2Cl4
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