Finding the mass?

A hot air balloon has a volume of 120 liters and holds air at a pressure of 101.325 kPa. If the balloon is filled with cold air (22 C), what is the mass of air inside the balloon? Use 28 for the molecular weight of air.

Thanks!

1 Answer
Feb 27, 2018

Well...#n=(PV)/(RT)#..and we have all the data....

Explanation:

#"Mass of air"=(120*Lxx1*atmxx28*g*mol^-1)/(0.0821*(L*atm)/(K*mol)*295*K)=138.7*g#

I used #"atmosphere"# for #"kilopascals"# because I could not be bothered to find the gas constant for kilopascals....#R=0.0821*L*atm*K^-1*mol^-1# is the constant that stuck in my head...and #1*atm-=101.325*kPa#.