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Question
Write scientific reason.
In a group, the size of the atom increases as it goes down from the top.
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Solution
- While going down from the top to bottom in a group, a number of shells increases.
- The outermost electrons go farther and farther from the nucleus, extending the radius and ultimately increasing the size of the atom even though the nuclear charge increases.
Hence, in a group, the size of the atom increases as it goes down from the top.
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