Question

On moving from left to right in a period of the periodic table, the atomic number of elements increases. What happens to the size of atoms of elements on moving from left to right in a period?

(a) increases
(b) decreases
(c) remain the same
(d) first increases then decreases

Answer 1

(b) Decreases.
The size of the atom decreases on moving from left to right in a period of the periodic table. With an increment in the atomic number, both the proton number and the nuclear positive charge increase. As the nucleus attracts the outermost electron, the size of the atom decreases.