A Rigid Cylinder with a Movable Piston Contains a Sample of Hydrogen Gas

Calculation of Sample Volume at STP

A rigid cylinder with a movable piston contains a sample of hydrogen gas at 330 K with a pressure of 150 K PA and a volume of 3.50 L. We need to determine the volume of the sample at STP.

Question:

Answer:

The volume of gas at STP is 4.3 L.

Explanation:

Initial temperature of gas = 330 K

Initial pressure = 150 Kpa (150/101.325 ≈ 1.4804 atm)

Initial volume = 3.5 L

New pressure = 1 atm

New temperature = 273.15 K

To Find: New volume

Formula

P₁V₁ / T₁ = P₂V₂ / T₂

Solution:

V₂ = P₁V₁. T₂ / T₁ . P₂

V₂ = 1.4804 atm. 3.5 L. 273.15 K / 330 K . 1 atm

V₂ = 1415.3 L / 330

V₂ = 4.3 L

Therefore, the volume of gas at STP is 4.3 L.