Same chapter3 marksDifficulty: Medium
An element X has atomic number 12. Write its electronic configuration, its group and the formula of its chloride.
Periodic Properties and Variations of Properties
3 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.
Original Khojo Papers practice question — not from a past board paper.
Answer
Group 17, period 3, and it is a non-metal.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
It has three shells, so it is in period 3, and seven electrons in the outermost shell, which places it in group 17. Elements with seven valence electrons gain one electron readily and are non-metals.
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