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
Why are the noble gases placed in a separate group and why is their ionisation potential very high?
Original Khojo Papers practice question — not from a past board paper.
Answer
The noble gases have completely filled outermost shells, so they have no tendency to gain, lose or share electrons and form almost no compounds. Removing an electron would break that stable arrangement, which needs a great deal of energy, so their ionisation potentials are the highest in their periods.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
They are placed in group 18 at the right of the table.
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