Question

how atomic radius changes when moving from left to right along a period. Explain?

Answer 1

On moving from left to right , Atomic radius decreases , because the no. of electrons in the orbit and Protons​ in the nucleus increase so the attraction b/w nucleus and orbit increases .

Answer 2

Across a period from left to right, the covalent radius decreases. As you move from left to right across the periodic table, atoms have more electrons in their outer energy level and more protons in their nucleus. ... As you move down a group in the periodic table, the covalent radius increases. Atoms increase in size.

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