Question

A gas cylinder contains 320 g oxygen gas at 24.6 atm pressure and 27 degree celsius. What mass of oxygen would escape if first the cylinder were heated to 133 degree celsius and then the value were held open until the gas pressure was 1.00 atm, the temperature being maintained at 133 degree celsius ? (R = 0.0821 L. atm/K/mole).

Answer 1

initially, number of mole of oxygen, n = 320/32 = 10 mol

initial temperature, Ti = 27°C = 300K

final temperature, Tf = 133°C = 273 + 133 = 406K

initial pressure, Pi = 24.6 atm

final pressure , Pf = 1.00 atm

first we have to find volume of container, V = nRTi/Pi

= 10 × 0.0821 × 300/24.6

≈ 10Litre

now, Let remaining oxygen = n'

then, n' = PfV/RTf

= 1 × 10/(0.0821 × 406)

= 0.3 mol

so, mass of 0.3mol of oxygen = 0.3 × 32g = 9.6g

so, mass of oxygen would escape = 320 - 9.6 = 310.4 g