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प्रश्न
Write scientific reason.
Boron and oxygen elements are placed in the second period in periodic table.
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उत्तर
- Electronic configuration of boron is (2, 3). Electronic configuration of oxygen is (2, 6).
- Both boron and oxygen have electrons in the two shells, K and L.
- The elements with the same number of shells occupied by electrons belong to the same period.
Hence, boron and oxygen elements are placed in the second period in the periodic table.
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