Question

A sample of a compound has a total mass of 200.0 g. Phosphorus comprises87.28 g of the sample while oxygen comprises 112.72 g.a. Find the percent mass of phosphorus and oxygen in the sample.

Answer 1

To find the mass percent composition of an element, divide the mass contribution of the element by the total mass then multiply by 100.

The total mass = 200.0 g

Phosphorus mass = 87.28 g

Oxygen mass = 112.72 g

%composition of P:

=> (87.28 g/200.0g)*100

=> 43.64 %

%composition of O:

=> (112.72g/200.0 g)*100

=> 56.36 %