Question

Match list (Molecules) with list II (Boiling points) and select the correct answer
`{:("List I","List II"),((a)NH_3,"(1)290 K"),((b)PH_3,"(2)211 K"),((c )AsH_3,"(3)186 K"),((d)SbH_3,"(4)264 K"),((e)BiH_3,"(5)240 K"):}`
A. a-3, b-2,c-5, d -4,e-1
B. a -5, b -3, c-2, d-4, e - 1
C. a - 1,b-4,c -5, d-2, e-3
D. a- 1, b-2, c-3, d-4, e-5

Answer 1

Correct Answer - B
`NH_3` due to hydrogen bonding has higher boiling point than `PH_3`. From `PH_3` to `BiH_3`, boiling point increases as the size of the central atom increases and so van der Waals forces increase. The increase is so high that they have boiling points higher than `NH_3`. Hence the order of boiling points is `PH_3`lt `AsH_3`lt `NH_3` lt `SbH_3` lt`BiH_3`.
b-3,c-2, 2-5, d-4, e-1