Question

A sample of ammonia (NH3) gas is completely decomposed to nitrogen and hydrogen gases over heated iron wool. If the total pressure is 719 mmHg after the reaction, calculate the partial pressures of N2 and H2. Enter your answers in scientific notation.

Answer 1

539.3mmHg of H₂

179.7mmHg of N₂

Step-by-step explanation:

Ammonia, NH₃, reacts completely producing N₂ and H₂ thus:

2 NH₃ → N₂ + 3H₂

That means there are produced 4 moles of gases and 3 are of H₂ and 1 of N₂

Total pressure (Sum of pressures of N₂ and H₂) is 719mmHg. 3 parts are of H₂ and 1 of H₂

Thus, partial pressures of the products after reaction are:

719mmHg ₓ (3 H₂ / 4) = 539.3mmHg of H₂

719mmHg ₓ (1 N₂ / 4) = 179.7mmHg of N₂