The number of electrons an atom would gain or lose when forming ionic bonds. it can be positive, negative or zero.

In an ionic bond , an element will have to lose or gain electrons.

Explanation:

Ionic bond, also called electrovalent bond, type of linkage formed from the electrostatic attraction between oppositely charged ions in a chemical compound. Such a bond forms when the valence (outermost) electrons of one atom are transferred permanently to another atom. The atom that loses the electrons becomes a positively charged ion (cation), while the one that gains them becomes a negatively charged ion (anion).

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The number of electrons an atom would gain or lose when forming ionic bonds cannot be zero.

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