Question

At Boyle's temperature, the value of compressibility factor $Z=(\frac{P{V}_m}{RT}=\frac{V_{real}}{V_{ideal}})$ has a value of 1, over a wide range of pressure. This is because in the van der Waal's equation:

• A. The constant 'a' is negligible and not 'b'
• B. The constant 'b' is negligible and not 'a'
• C. Both the constants 'a' and 'b' are negligible
• D. The effect produced due to the molecular attraction is compensated by the effect produced due to molecular volume

Answer 1

The correct option is D The effect produced due to the molecular attraction is compensated by the effect produced due to molecular volume

The van der Waal's equation for n moles of gas is,
$(P+\frac{a{n}^2}{V^2})(V-nb)=nRT$
Boyle's temperature is the temperature where a real gas starts to behave like an ideal gas. At Boyle's temperature, the value of compressibility factor $Z=(\frac{P{V}_m}{RT}=\frac{V_{real}}{V_{ideal}})$ has a value of 1, over a wide range of pressure because the effect produced due to the molecular attraction is compensated by the effect produced due to molecular volume.