Question

Explain why the atomic size of elements increases from top to bottom in a group.

Answer 1

Answer:

This is caused by the increase in the number of protons and electrons across a period. One proton has a greater effect than one electron; thus, electrons are pulled towards the nucleus, resulting in a smaller radius. Atomic radius increases from top to bottom within a group. This is caused by electron shielding.

Answer 2

Answer:

because of addition of new electronic shells of a atom