KCET2024Chemistryp Block Elements (Group 15, 16, 17 & 18)
The correct decreasing order of boiling point of hydrogen halides is
Options
- AHF HCl HBr HI
- BHI HBr HCl HF
- CHF HI HBr HCl
- DHI HF HBr HCl
Correct answer
C. HF HI HBr HCl
Step-by-step solution
HF is hydrogen bonded, thus it has highest boiling point. The remaining hydrogen halides are gaseous and their boiling points depend on the van der Waals' forces. Greater the molecule mass, greater will be the van der Waals' forces. Hence higher is the boiling point. Thus, the correct order is HF HI HBr HCl .