KCET2023Chemistryp Block Elements (Group 15, 16, 17 & 18)
The correct decreasing order of basicity of hydrides of group- 15 elements is
Options
- ASbH ₃> AsH ₃> PH ₃> NH ₃
- BPH ₃> AsH ₃> SbH ₃> NH ₃
- CAsH ₃> SbH ₃> NH ₃> PH ₃
- DNH ₃> PH ₃> AsH ₃> SbH ₃
Correct answer
D. NH ₃> PH ₃> AsH ₃> SbH ₃
Step-by-step solution
In general, the basicity of group 15 hydrides decreases on moving down the group from NH ₃ to SbH ₃ . This is due to the increasing size of the central atom and the decreasing availability of lone pair for donation. Thus, the correct order of basicity of hydrides is NH ₃> PH ₃> AsH ₃> SbH ₃