Same chapter3 marksDifficulty: Medium
An element has the electronic configuration 2, 8, 7. State its group, its period and whether it is a metal or a non-metal.
Periodic Properties and Variations of Properties
2 marksDifficulty: Medium
Arrange Li, Na and K in increasing order of ionisation potential and give the reason.
Original Khojo Papers practice question — not from a past board paper.
Answer
K < Na < Li. Down group 1 the atoms get larger and the outermost electron is further from the nucleus and better shielded, so it is removed more easily.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
This is also why potassium is the most reactive of the three.
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