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Question
Write scientific reason.
In same period, boron and oxygen elements have different atomic size.
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Solution
- Boron and oxygen are placed in the same period. However, their atomic numbers are different.
- Atomic number of boron is 5 and that of oxygen is 8.
- In a period, as the atomic number increases from boron to oxygen, the positive charge on the nucleus increases. At the same time, electrons get added in the same outermost shell. This increases effective nuclear charge.
- As a result, electrons are attracted closer to the nucleus decreasing the size of the oxygen atom.
Hence, in same period, boron and oxygen elements have different atomic size.
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