Question:
Compressibility factor, Z, of a gas is given as Z = PV/ nRT
(i) What is the value of Z for an ideal gas?
(ii) For real gas what will be the effect on the value of Z above Boyle’s temperature?
Solution:
(i) Compressibility factor, Z is defined as the ratio of the product of pressure and volume to the product of the number of moles, gas constant and temperature.
For an ideal gas, the value of Z is 1.
(ii) Above Boyle’s temperature, PV is greater than nRT for real gases so, the value of Z will also be greater than 1 i.e Z>1, which shows the positive deviation in the
compressibility factor above Boyle’s temperature.