Respuesta :

The positive ionic radius is smaller than the neutral atomic radius.

Answer : When an electron is lost then the atomic radius is, decreases.

Explanation :

Atomic radius of an atom is defined as the total distance from the nucleus to the valence shell of the atom.

As moving from left to right in a period, more electrons are added in the same shell and the attraction between the last electron and nucleus increases, which results in the shrinkage of size of an atom.

Thus, atomic radii from the left to right across a period tend to decrease.

As moving from top to bottom in a group, there is an addition of shell around the nucleus and the outermost shell gets far away from the nucleus and hence, the distance between the nucleus and outermost shell increases.

Thus, atomic radii from the top to bottom in a group tend to increases.

When atom loses an electron then it becomes positively charged and the atomic radius of positively charged ion is lower than neutral atom.

When atom gains an electron then it becomes negatively charged and the atomic radius of negatively charged ion is more than neutral atom.

Hence, when an electron is lost then the atomic radius is, decreases.