How would you calculate the empirical formula of acetic acid (CH3COOH)?

1 Answer
Nov 12, 2015

You would divide the numbers of each atom in the molecular formula by their highest common factor.

Explanation:

The empirical formula is the simplest possible formula for a compound.

The subscripts of the elements in the empirical formula must be in the smallest possible ratio.

We can write the molecular formula "CH"_3"COOH" as "C"_2"H"_4"O"_2.

The ratios of "C:H:O" are 2:4:2.

The highest common factor of 2 and 4 is 2.

We can divide each of these numbers by 2 to get the ratio

"C:H:O" = 1:2:1

The empirical formula of acetic acid is then "CH"_2"O".