Question

Explain, in detail, why atomic radii do not increase uniformly with increasing atomic number. Give specific examples in your answer.

Answer 1

in groups from top to bottom size increases .distance between center of the nucleas and valence shell increases atomic radius increases but in periods from Na , mg and Al.. across period atomic number increases nuclear charge increases i.e electrons are attracted by proton increases and hence atomic radius decreases.

in groups also atomic radius also not in regular trend due increasing of nuclear charge .example 4th group transition elements.Ti ,Zr ,Hf and Ru ..