An organic compound has the empirical formula \(CH_{2}\). If its molar mass is 42\(gmol^{-1}\), what is its molecular formula?  (C = 12.0, H = 1.0)

A.

\(C_{2}H_{4}\)

B.

\(C_{3}H_{4}\)

C.

\(C_{3}H_{6}\)

D.

\(C_{4}H_{8}\)

Correct answer is C

Given the molecular formula, \(CH_{2}\).

The empirical formula will be \((CH_{2})n\)= 42

\((12+(2\times1))n =42\)

⇒ \(14n =42\)

n = 3, hence the empirical formula is \(C_{3}H_{6}\)