Q. A hydrocarbon contains 10.5 g carbon and 1 g hydrogen. Its 2.4 g has 1 L volume at 1 atm and$127℃$. Hydrocarbon is
A) $C_{6}H_{7}$
B) $C_{6}H_{8}$
C) $C_{5}H_{6}$
D) $C_{6}H_{6}$
Explanation
(a)
$C = 10.5\ g = \frac{10.5}{12}mol = 0.87\ mol$
$H = 1\ g = \frac{1}{1}mol = 1\ mol$
$\therefore\left( C_{0.87}H_{1} \right)_{7} = C_{6.09}H_{7} \approx C_{6}H_{7}$
$pV = nRT = \frac{w}{m}RT$
$1 \times 1 = \frac{2.4}{m} \times 0.082 \times 400$
$m = 79$
Hence, the hydrocarbon is $C_{6}H_{7}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.