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Question
An organic compound contains H = 4.07%, Cl = 71.65% chlorine and remaining carbon. Its molar mass = 98.96. Find its molecular formula.
Solution
Empirical formula weight = 12 + (2 × 1) + 35.5
= 49.5
Molar mass = 98.96
n = `"Molar mass"/"Empirical formula mass"`
= `98.96/49.5`
= 2
∴ Molecular formula = 2 [CH2Cl] = C2H4Cl2
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