Find the mass of phosphorus required to obtain phosphorus oxide V, weighing 28.4 grams.

The synthesis reaction of phosphorus oxide is described by the following chemical reaction equation:

4P + 5O2 = 2P2O5;

4 phosphorus atoms interact with 5 oxygen molecules. In this case, 2 molecules of phosphorus oxide are synthesized.

Let’s calculate the chemical amount of a substance in phosphorus oxide weighing 28.4 grams.

M P2O5 = 31 x 2 + 16 x 5 = 142 grams / mol;

N P2 O5 = 28.4 / 142 = 0.2 mol;

To synthesize such an amount of oxide, it is necessary to oxidize 0.2 x 2 = 0.4 mol of phosphorus.

Let’s calculate its weight.

To do this, we multiply the amount of the substance by its molar weight.

M P = 31 grams / mol;

m P = 31 x 0.4 = 12.4 grams;