MGIMS WARDHA MGIMS WARDHA Solved Paper-2010

An organic substance containing carbon, hydrogen and oxygen gave the following percentage composition. \[C=40.687%;\text{ }H=5.085%\text{ }and\text{ }O=54.228%\] What is the empirical formula of the compound?

A) \[C{{H}_{3}}O\]

B) \[{{C}_{2}}{{H}_{2}}O\]

C) \[C{{H}_{4}}O\]

D) \[{{C}_{2}}{{H}_{3}}{{O}_{2}}\]

Correct Answer: D

Solution :

Symbol	Percentage	Relative no. of moles	Simplest molar ration	Simplest whole no. molar ratio
\[C\]	\[40.687\]	\[\frac{40.687}{12}=3.390\]	\[\frac{3.390}{3.389}=1\]	2
\[H\]	\[5.085\]	\[\frac{5.085}{1}=5.085\]	\[\frac{5.085}{3.389}=1.5\]	3
\[O\]	\[54.228\]	\[\frac{54.228}{16}=3.389\]	\[\frac{3.389}{3.389}=1\]	2

Hence, the epitomical formula of the compound is\[{{C}_{2}}{{H}_{3}}{{O}_{2}}\].