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Question
How do electronic configurations of elements change in second period of periodic table with increase in atomic numbers?
Solution
| Element in the second period | Li (3) | Be (4) | B (5) | C (6) | N (7) | O (8) | F (9) | Ne(10) |
| Electronic configuration | 2,1 | 2,2 | 2,3 | 2,4 | 2,5 | 2,6 | 2,7 | 2,8 |
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| Period No. | ||
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| 5 | Rb(37) | Sr(38) |
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| K | |
| Rb | |
| Cs | |
| Fr | |
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