Citric acid, the compound responsible for the sour taste of lemons, has an elemental composition of 37.51% C, 4.20% H, and 58.29% O Calculate the empirical formula of citric acid.

The empirical formula of citric acid is C6H8O7

Explanation:

Step 1: Data given

Suppose the compound has a mass of 100.0 grams

The compound contains:

37.51 % C = 37.51 grams C

4.20 % H = 4.20 grams H

58.29 % O = 58.29 grams O

Molar mass of C = 12.01 g/mol

Molar mass of H = 1.01 g/mol

Molar mass of O = 16.00 g/mol

Step 2: Calculate moles

Moles = mass / molar mass

Moles C = 37.51 grams / 12.01 g/mol

Moles C = 3.123 moles

Moles H = 4.20 grams / 1.01 g/mol

Moles H = 4.16 moles

Moles O = 58.29 grams / 16.00 g/mol

Moles O = 3.643 moles

Step 3: Calculate mol ratio

We divide by the smallest amount of moles

C: 3.123 moles / 3.123 moles = 1

H: 4.16 moles / 3.123 moles = 1.33

O: 3.643 moles / 3.123 moles = 1.17

If we multiply those by 6 we find the coefficients of the empirical formula

C6H8O7

The empirical formula of citric acid is C6H8O7