Question

A real gas is supposed to obey the gas equation P(V – nb) = nRT at STP. If one mole of a gas occupies 25 dm3 volume at STP. Calculate compressibility factor for gas

Answer 1

Answer:

Explanation:

Given P(V−b)=nRT

1×(25−b)=1×0.0821×273 ltbr gt(∵V=25dm3=25litre)

b=2.586litre

Also diameter of molecule d=2r ltbr gtWe have b=4×N× Volume of molecule

=4×6.023×1023×43πr3

∴2.586=4×6.023×1023×43×227(d2)3

∴d=1.270×10−8cm

(b) Given P(V−b)=nRT,PV−Pb=nRT

PVnRT−PbnRT=1

or Z−PbnRT=1

(∵PVnRT=Z compressibility factor) ltbr gt or Z=1+PbnRT=1+1×2.5861×0.0821×273=1.115