Q5 of 49 Page 124

How does the atomic size of the elements very along a period?

The atomic size increases on moving down the group. This is because of the increase in a number of shells due to which the distance between the outermost electron and the nucleus increases.

The atomic size decreases on moving along a period. This is because of the increase in the effective nuclear charge on moving from left to right which tends to pull the electrons towards the nucleus.


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(i) 2,8 (ii) 2,5

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