Calculate the amount of sodium sulfide substance if sulfur with a mass of 14.4 g (containing 5% impurities)

Calculate the amount of sodium sulfide substance if sulfur with a mass of 14.4 g (containing 5% impurities) enters into a reaction with sodium.

1. Let us write down the equation for obtaining sodium sulfide:

2Na + S = Na2S;

2.Calculate the mass of sulfur in its sample:

m (S) = w (S) * m (sample);

w (S) = 1 – w (impurities) = 1 – 0.05 = 0.95;

m (S) = 0.95 * 14.4 = 13.68 g;

3.Calculate the chemical amount of sulfur:

n (S) = m (S): M (S) = 13.68: 32 = 0.4275 mol;

4.determine the amount of sodium sulfide formed:

n (Na2S) = n (Na): 2 = 0.4275: 2 = 0.21375 mol.

Answer: 0.21375 mol.