Which of the following elements is most likely to form a +3 cation?

Question

Lithium
Boron
Nitrogen
Fluorine

Answer 1

Boron.

Lithium (1s2 2s1) is one electron above a complete shell, so will form a +1 cation readily, but it will take significantly more energy to strip away the second and third electrons.

Boron (1s2 2s2 2p1) is three electrons above a completed shell, so will form a +3 cation readily.

Nitrogen (1s2 2s2 2p3) is five electrons above a completed shell, and 3 electrons below the next, so the most probable ion is a -3 anion.

Fluorine (1s2 2s2 2p5) is one electron short of a completed shell, and will tend to form a -1 anion.

Answer 2

their is only in group 3 element will form +3 cation when it ionization is occur.because the outer most electron will release to form a stable electro configuration or an octet position.