NEETChemistryp Block Elements (Group 15, 16, 17 & 18)
What is the trend in ionisation enthalpy as you move down Group 17 (halogens)?
Options
- AIncreases
- BDecreases
- CRemains constant
- DVaries unpredictably
Correct answer
B. Decreases
Step-by-step solution
Ionisation enthalpy decreases as you move down Group 17 (halogens) due to the increase in atomic size and the addition of electron shells.