# Q.89. The gas having the least value of van der Waal constant 'b' is (1) He (2) ${H}_{2}$ (3) ${N}_{2}$ (4) Xe

Dear Student,

The Vanderwaal constant 'b' depends on the molecular size. Since, He has the smallest size as it is monoatomic whereas (2) and (3) are diatomic.Xe is also monoatomic but its size is greater than He.