Question

A compound containing phosphorus and oxygen has a molar mass of 219.9 g/mol and an empirical formula of p2o3.

Answer 1

I guess the question here is to obtain the chemical formula of the compound. We can as follows:

P2xO3x

Let x the number to be multiplied to each atom in the chemical formula.

2x(90.97) + 3x(16) = 219.9
x = 1

Therefore, the chemical formula would be P2O3. Hope this helps.