Positive deviation from ideal behaviour takes place because of

Options

A. molecular interaction between atoms and `PV//nRT gt 1`
B. molecular interaction between atoms and `PV//nRT lt 1`
C. finite size of atoms and `PV//nRT gt 1`
D. finite size of atoms and `PV//nRT lt 1`

Answer

B

Explanation

Observed exerted by an ideal gas under similar conditions. This is due to molecular interactions between molecules of the real gas. Considering only pressure correction, van der Waal's equation reduces to
`(P + (an)/(V^(2))) V = nRT`
`PV + (an)/(V) = nRT`
Thus, `nRT gt PV` ( `:. a, n` and V are all `+ve`) or `1 gt (PV)/(nRT)` (`:. n, R` and T are all +ve)