A 20-cm-diameter cylinder that is 40 cm long contains 50 g of oxygen gas at 20C.

What is the number density of the oxygen? in m^-3
What is the reading of a pressure gauge attached to the tank? in kPa

1 answer

p•V =m•R•T/μ,
T= 293
μ =32000
p = m•R•T/V•μ
Density = m/V = p•μ/R•T