Calculate the mass of phosphorus and the volume of oxygen that will be required to obtain P2O5

Calculate the mass of phosphorus and the volume of oxygen that will be required to obtain P2O5, the mass of which is 71 grams. Formula 5O2 + 4P = 2P2O5.

1.5O2 + 4P = 2P2O5;

2. find the chemical amount of phosphorus:

n (P2O5) = m (P2O5): M (P2O5);

M (P2O5) = 31 * 2 + 16 * 5 = 142 g / mol;

n (P2O5) = 71: 142 = 0.5 mol;

3. according to the equation, the amounts of P and P2O5 are related as 4: 2, we find the amount of phosphorus:

n (P) = n (P2O5) * 2 = 0.5 * 2 = 1 mol;

4.The mass of the required phosphorus will be:

m (P) = n (P) * M (P) = 1 * 31 = 31 g;

5.the coefficients in front of O2 and P2O5 are related as 5: 2, we calculate the amount of oxygen:

n (O2) = n (P2O5) * 5: 2 = 0.5 * 5: 2 = 1.25 mol;

6.determine the volume of oxygen:

V (O2) = n (O2) * Vm;

V (O2) = 1.25 * 22.4 = 28 dm3.

Answer: 31 g; 28 dm3.