White phosphorus, P4, spontaneously bursts into flame when exposed to oxygen. If 6.500 g of white phosphorus reacts with oxygen to form 11.54 g of a phosphorus oxide, what is the empirical formula of this oxide?

Empirical formula for the oxide is P₂O₃

Explanation:

Oxides from P, are:

P₂O; P₂O₃; P₂O₅; P₂O₇; P₄O₆; P₄O₁₀

The reaction is:

P₄ + 3O₂ → P₄O₆

Ratio between the white phosphorus and the oxide is 1:1

Molar mass P₄ = 123.89 g/m

Mass / Molar mass = mole

6.5 g / 123.89 g/m = 0.0524 mole P₄

0.0524 mole of P₄O₆ have been formed.

Molar mass P₄O₆ = 219.89 g/m

Mol. molar mass = mass

0.0524 mole. 219.89 g/m = 11.52 g