The mole percent composition of welding gas InomaxPLUS is 63

The mole percent composition of welding gas InomaxPLUS is 63% Argon gas, 35% Helium and 2% Carbon Dioxide.

(a) For a sample at 298 K of 22.4 L of welding gas at 760 mm Hg total pressure, calculate

(1) the pressure of each gas in the sample

(2) the mass of Ar, He, CO2 in the sample.

(b) If the volume of the container is reduced to 15.0 L and the pressure remains at 760 mm Hg total pressure. Calculate the temperature of the gas mixture

Solution

mole fraction

Ar = 0.63

He = 0.35

Co2 = 0.02

pAr = 760*0.63 = 478.8 mmHg

pHe = 266 mmHg

pCO2 = 15.2mmHg

mass of Ar = 40*0.63 = 25.2g

He = 2*0.35 = 0.7g

CO2 = 0.02*44 = 0.88g

V1/T1 = V2/T2

T2 = 15/22.4 * 298 = 199.55K