Question

Which of the following molecules has/have the same empirical formula as acetic acid (HC2O2H3)? (a) Formaldehyde (b) Benzaldehyde (c) Glucose

Answer 1

Answer: Option (a) is the correct answer.

Explanation:

A chemical formula which represents proportions between the elements present in a compound is known as empirical formula.

When chemical or molecular formula is able to be reduced to smaller whole-number ratio of the elements then both molecular and empirical formulas are considered to be the same.

Relation between molecular formula and empirical formula is as follows.

               Molecular formula = n × Empirical formula

where, n is an integer.

Chemical formula of acetic acid is $CH_{3}COOH$.

Chemical formula of formaldehyde is $CH_{2}O$. It is the smaller whole-number ratio of molecular formula of acetic acid.

Chemical formula of Benzaldehyde is $C_{6}H_{5}COOH$.

Chemical formula of glucose is $C_{6}H_{12}O_{6}$.

Thus, we can conclude that formaldehyde molecules has/have the same empirical formula as acetic acid ($HC_{2}O_{2}H_{3}$).