Question

Positive deviation from ideal behaviour takes place because of
A. Molecular interactioin 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 1

Correct Answer - C
For position deviation `: PV = nRT +nPbimplies (PV)/(nRT)= 1+ (PB)/(RT)`
Thus, the factor nPb is responsible for increasing the PV value, above ideal value, b is actually the effective volume of molecule. So, it is the finite size of molecules that leads to the origin of b and hence positive deviation at high pressure.