Question

Ammonia gas has a molar mass of approximately 17 grams per mole. At 290 K and 1.2 atm, a sample of ammonia has a volume of 3.7 L. In three to five sentences, explain how you can find the mass of the ammonia. Then, given R = 0.0821 L·atm/(mol·K), calculate the mass.

Answer 1

To calculate the mass of ammonia, use the ideal gas law PV = nRT to find the number of moles and multiply by the molar mass of ammonia (approximately 17 grams per mole), resulting in a mass of 3.1178 grams.

Step-by-step explanation:

To find the mass of the ammonia gas, we can use the ideal gas law which is expressed as PV = nRT.

Here, P stands for pressure, V is volume, n is the number of moles, R is the ideal gas constant, and T is temperature in Kelvin.

Using the given values (P = 1.2 atm, V = 3.7 L, R = 0.0821 L·atm/(mol·K), T = 290 K), we can calculate the number of moles of ammonia.

We then multiply the number of moles by the molar mass of ammonia, which is approximately 17 grams per mole, to find the mass of the ammonia.

Solving for n we get n = PV/RT.

Substituting the given values we find n = (1.2 atm × 3.7 L) / (0.0821 L·atm/(mol·K) × 290 K)

= 0.1834 mole

. The mass of the ammonia is therefore 0.1834 moles × 17 g/mol = 3.1178 grams.