Question

A gas at constant volume has a pressure of 3.20 atm at 300. K. What will be the pressure of the gas at 290. K?

Answer 1

• From the general law of gases: PV = nRT,

where P is the pressure (atm),

V is the volume (L),

n is the number of moles,

R is the general gas constant (8.314 L.atm/mol.K),

T is the temperature in Kelvin

• at constant volume of the gas: P1T2 = P2T1

P1 = 3.20 atm, T1 = 300 K, T2 = 290 K, P2 = ??

(3.20 atm)(290 K) = P2(300 K)

P2 = (3.20 atm)(290 K)/ (300 K) = 3.093 atm