Question

Graph of variation of atomic radius with atomic number across period

Answer 1

Hey friend, Harish here.

Here is your answer:

Across the period ( From Left to Right ) the atomic radii of the elements decreases. Whereas the atomic number increases. So, We can conclude from this that, the atomic radii decreases with increase in atomic number.

Reason:

This is due to the shielding of the electrons in the atoms. The nucleus has its character positive charge, but due to shielding by core electrons the total positive charge is not completely felt by the electrons, so the actual net positive charge felt by the valence electron has its own name and is called the effective nuclear charge . This effective nuclear charge, largely effects the size of the atom. The general trend of the periodic table is that as you go down a group, and go from right to left, the Zeff (effective nuclear charge) decreases, and you see an increase in the size of the atom.

(Graph and Periodic table image attached , go through simultaneously for complete understanding.)

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Hope my answer is helpful to you.