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प्रश्न
Write scientific reason.
Boron and oxygen elements are placed in the second period in periodic table.
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 periodic table.
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