A 2.50 L sample of a gas at 1.00 atm is subjected to 1.25 atm of pressure at constant temperature. What is the new volume of the gas?

2.0 L.

Explanation:

We can use the general law of ideal gas: PV = nRT.

where, P is the pressure of the gas in atm.

V is the volume of the gas in L.

n is the no. of moles of the gas in mol.

R is the general gas constant,

T is the temperature of the gas in K.

If n and T are constant, and have two different values of V and P:

P₁V₁ = P₂V₂

P₁ = 1.0 atm, V₁ = 2.5 L.

P₂ = 1,25 atm, V₂ = ? L.

∴ V₂ = P₁V₁/P₂ = (1.0 atm) (2.5 L) / (1.25 atm) = 2.0 L.