Read the paragraph carefully and answer the following questions:
Real gases deviate from ideal behaviour because of the following two faulty assumptions of kinetic theory.
(I) The actual volume occupied by molecules is negligible as compared to the total volume of the gas.
(II) The forces of attraction and repulsion between molecules of the gas are negligible. The extent of deviation of a real gas from ideal behaviour is expressed in terms of compressibility factor (z).
Hence, suitable corrections were applied to the ideal gas equation so that it can also explain the behaviour of real gases. The equation obtained by applying the two corrections to the usual gas equation is known as van der Waal equation.
A Volume correction Corrected (ideal) volume = (V - b) Where b is the effective volume of the molecules.
B. Pressure correction (intermolecular attraction corection). Corrected (ideal) pressure = P + P
However, `P=(a)/(V^(2))`
`therefore` The van der Waal's equation becomes `(P+(an^(2))/(V^(2)))(V-nb)=nRT`
0.5 value of compressibility factor (z) indicates that the gas

Options

A. shows positive deviation from the ideal gas
B. negative deviation from the ideal gas behaviour
C. either of the two
D. the factor is insufficient

Answer

B