Ammonia gas has a molar mass of approximately 17 grams per mole. At 290K and 1.2 atm, a sample of ammonia has a volume of 3.7 L.

Question

In three to five sentences, explain how you can find the mass of the ammonia. Then, given R=0.0821L⋅atmmol⋅K
, calculate the mass.

(4 points)

Answer 1

To find the mass of the ammonia gas, you can use the ideal gas law equation: PV = nRT. Rearrange the equation to solve for n (number of moles): n = PV/RT. Substitute the given values into the equation: n = (1.2 atm * 3.7 L) / (0.0821 Latm/molK * 290 K) ≈ 0.1786 moles. Lastly, multiply the number of moles by the molar mass of ammonia (17 g/mol) to find the mass: 0.1786 moles * 17 g/mol ≈ 3.04 grams. Therefore, the mass of the ammonia gas is approximately 3.04 grams.