Question

A tank contains 25.1 kg of air, 21.7 kg of CO2 and 41.6 kg of SO2. A gage on the tank reads the pressure of the mixture is 4.7 atm. at 22 °C. What is the partial pressure of Air in the tank (atm) ?(round to 2 decimal places)

Answer 1

Total pressure = 4.7 atm

Molar mass of air = 29 g/mol

Moles of air = 25.1 kg * ( 1000 g / 1 kg) * ( 1 mole / 29 g)

= 865.5 moles

Moles of CO2 = 21.7 kg * ( 1000 g / 1 kg ) * ( 1mole / 44.01 g)

= 493.1 moles

Moles of SO2 = 41.6 kg * ( 1000 g / 1 kg) * ( 1 mole / 64.1 g)

= 649 moles

Mole fraction of air = moles of air / total moles

= 865.5 mol / (865.5 + 493.1 + 649)

= 0.431

Partial pressure of air = mole fraction * total pressure

= 0.431 * 4.7 atm

= 2.03 atm