How much oxygen reacts with phosphorus if 142 g of diphosphorus penta oxide is formed?

Diphosphorus pentoxide – phosphoric anhydride – phosphorus (V) oxide – a higher phosphorus oxide with the formula P2O5.

Formed as a result of the combustion of phosphorus in oxygen. Reaction equation:

4 P + 5 O2 = 2 P2O5

Using the reaction equation, we compose the proportion and find the amount of oxygen. Molar mass of phosphoric anhydride = 142 g / mol.

X mol of oxygen corresponds to 142 g of P2O5, as

5 mol of oxygen corresponds to 2 * 142 g / mol P2O5

X = (142 * 5) / (2 * 142) = 2.5 mol.

Answer: the amount of oxygen is 2.5 mol.