Question

Calculate the empirical formula of a compound that is 42.9% Carbon and 57.1% Oxygen.

Answer 1

Answer:

CO.

Explanation:

Assuming the given percentages are by mass, we can solve this problem via imagining we have 100 g of the compound, if that were the case we would have:

• 42.9 g of C

• 57.1 g of O

Now we convert those masses into moles, using the elements' respective molar masses:

• 42.9 g of C ÷ 12 g/mol =  3.57 mol C

• 57.1 g of O ÷ 16 g/mol =  3.58 mol O

As the number of C moles and O moles is roughly the same, the empirical formula for the compound is CO.