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Question

Give reasons for the following:
Atomic size decreases across a period but increases down a group of the periodic table.

Periodic Table

Chemistry, Class 10, ICSE, J Dalal

July 25, 2024

Answer

Across a Period: Atomic size decreases as nuclear charge increases, pulling electrons closer to the nucleus.

Down a Group: Atomic size increases because more shells are added, outweighing the effect of increased nuclear charge.

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