Find the mass of oxide if 62 g of phosphorus is burned in 11.2 liters of oxygen.

The production of phosphorus oxide is described by the following chemical reaction equation (CCR):

4P + 5O2 = 2P2O5;

4 moles of phosphorus react with 5 moles of oxygen. In this reaction, 2 moles of phosphorus oxide are synthesized.

Let’s calculate the chemical amount of a substance contained in phosphorus weighing 62 grams.

M P = 31 grams / mol;

N P = 62/31 = 2 mol;

Let’s calculate the chemical amount of oxygen. To do this, we divide its volume by the volume of 1 mole of gas (assuming a volume of 22.4 liters).

N O2 = 11.2 / 22.4 = 0.5 mol;

0.5 mol of oxygen will react with 0.5 / 5 x 4 = 0.4 mol of phosphorus. In this case, 0.4 / 2 = 0.2 mol of its oxide will be synthesized.

Let’s calculate its weight. To do this, we multiply the amount of the substance by the weight of 1 mole (its molar weight).

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

m P2O5 = 0.2 x 142 = 28.4 grams;