Same chapter3 marksDifficulty: Medium
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Periodic Properties and Variations of Properties
3 marksDifficulty: Medium
Define ionisation potential and state how it varies across a period.
Original Khojo Papers practice question — not from a past board paper.
Answer
The ionisation potential is the energy required to remove the most loosely held electron from an isolated gaseous atom. Across a period it increases from left to right, because the atomic size decreases and the nuclear charge increases, so the outermost electron is held more firmly.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
It decreases down a group for the opposite reasons.
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