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प्रश्न
Write scientific reason.
Lithium and sodium are included in the same group in periodic table.
उत्तर
- Electronic configuration of lithium is (2, 1). Electronic configuration of sodium is (2, 8, 1).
- Both lithium and sodium have single electron in their outermost shell.
- Their valency is 1.
- In the periodic table, elements belonging to the same group have the same valency. Hence, lithium and sodium are included in the same group in periodic table.
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