Question

An elemwhat happend to the size of atom down a group and across a period

Answer 1

The atomic size increases from the top to the bottom in any group as a result of increases in all of the three factors. (As the number of energy levels increases, the size must increase.) Going across a period (from left to right), the number of protons increases and therefore the nuclear charge increases.

Atomic size gradually decreases from left to right across a period of elements. This is because, within a period or family of elements, all electrons are added to the same shell. However, at the same time, protons are being added to the nucleus, making it more positively charged.

Answer 2

The atomiz size decreases across the period as nuclear charge increase.

The atomiz size increases down a group as no. Of shells increases.

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