A closed vessel of volume 80 litres contains 0.5 N of gas at a pressure of 150 kN/m2. If the gas is compressed isothermally to half its volume, determine the resulting pressure.

The resulting pressure of the gas when its volume decreases is 300 kN/m².

Explanation:

Given;

initial volume of the gas, V₁ = 80 L

number of moles of the gas, n = 0.5 moles

initial pressure of the gas, P₁ = 150 kN/m² = 150 kPa

Determine the constant temperature of the gas using ideal gas equation;

PV = nRT

where;

R is ideal gas constant = 8.315 L.kPa/K.mol

T is the constant temperature

When the gas is compressed to half of its volume;

new volume of the gas, V₂ = ¹/₂ V₁

                                             = ¹/₂ x 80L = 40 L

The new pressure, P₂ is calculated as;

Therefore, the resulting pressure of the gas when its volume decreases is 300 kN/m².