Question

Correct order of decreasing thermal stability is
A. `NH_(3) gt PH_(3) gt AsH_(3) gt SbH_(3)`
B. `PH_(3) gt NH_(3) gt AsH_(3) gt SbH_(3)`
C. `AsH_(3) gt PH_(3) gt NH_(3) gt SbH_(3)`
D. `SbH_(3) gt AsH_(3) gt PH_(3) gt NH_(3)`

Answer 1

Correct Answer - A
The thermal stability of hydrides of nitrogen family or group 15 elements decreases on moving downwards in the group. Therefore, `NH_(3)` is the most stable and `BiH_(3)` is the least stable. The stability of the hybrides of group 15 elements decreases in the order : `NH_(3) gt PH_(3) gt AsH_(3) gt SbH_(3) gt BiH_3`