Question

An organic compound contains carbon, hydrogen and oxygen. Its elemental analysis gave C, 38.71% and H, 9.67%. The empirical formula of the compound would be

• A. CHO
• B. $C{H}_{4}O$
• C. $C{H}_{3}O$
• D. $C{H}_{2}O$

Answer 1

Answer: (C)

Element	%	Atomic mass	mole ratio	simple ratio
$C$	38.71	$12$	$\frac{38.71}{12}=3.22$	$\frac{3.22}{3.22}=1$
$H$	9.67	$1$	$\frac{9.67}{1}=9.67$	$\frac{9.67}{3.22}=3$
$O$	51.62	$16$	$\frac{51.62}{16}=3.22$	$\frac{3.22}{3.22}=1$

Hence empirical formula of the compound would be $C{H}_{3}O$ .