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प्रश्न
Write scientific reason.
Lithium and sodium are included in the same group in periodic table.
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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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संबंधित प्रश्न
Fill in the blank:
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Fill in the blank:
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| Group No. → | 1 | 2 | 13 | 14 | 15 | 16 | 17 | 18 |
| Period ↓ | ||||||||
| 2 | A | B | ||||||
| 3 | E | D | F | C |
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