Q13.4 An oxygen cylinder of volume litres has an initial gauge pressure of atm and a temperature of . After some oxygen is withdrawn from the cylinder, the gauge pressure drops to atm and its temperature drops to . Estimate the mass of
oxygen taken out of the cylinder (, molecular mass of ).
Initial volume, V1 = Volume of Cylinder = 30 l
Initial Pressure P1 = 15 atm
Initial Temperature T1 = 27 oC = 300 K
Initial number of moles n1 inside the cylinder is
Final volume, V2 = Volume of Cylinder = 30 l
Final Pressure P2 = 11 atm
Final Temperature T2 = 17 oC = 290 K
Final number of moles n2 inside the cylinder is
Moles of oxygen taken out of the cylinder = n2 -n1 = 18.28 - 13.86 = 4.42
Mass of oxygen taken out of the cylinder m is