Question

An unknown compound is found to have 5.34 grams of oxygen, 3.99 grams of carbon, and 0.67 grams of hydrogen. What is the empirical formula of

this compound? If the molecular mass for the compound is 60.052 amu (or g/mol), what is the molecular formula?
Make sure to show all of your work on paper for credit.

Answer 1

Empirical formula:CH2O

Molecular formula:C2H4O2

Explanation: For empirical formula: Find mass to mole ratio

so we divide each of th c,h,o respective mass with their molar mass giving us the ratio of approximately 0.3:0.6:0.3

which simplifies to 1:2:1 giving us CH2O

To find the molecular formula:

We find the molar mass of empirical formula which is 30 (half the molecular mass) so we multiply the empirical formula by 2 giving us C2H4O2