Calculate the amount of substance and mass of phosphorus required to obtain 71g of phosphorus (V) oxide.

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 71 grams.

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

N P2O5 = 71/142 = 0.5 mol;

To synthesize such an amount of oxide, it is necessary to oxidize 0.5 x 2 = 1 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 1 = 31 grams;