Question

which quantity determines how two atoms bond?

Their total number of valence electrons
the difference in the number of valence electrons
the difference in their electronegativities
the sum of their electronegativities

Answer 1

The quantity that primarily determines how two atoms bond is **the difference in their electronegativities**.

Electronegativity is a measure of an atom's ability to attract and hold onto electrons. When two atoms bond, the difference in electronegativity can indicate whether the bond will be ionic, polar covalent, or nonpolar covalent.

- A large difference in electronegativity typically leads to ionic bonding, where one atom completely transfers electrons to another.
- A moderate difference results in polar covalent bonding, where electrons are shared unequally.
- A small difference indicates nonpolar covalent bonding, where electrons are shared equally.

While the total number of valence electrons, the difference in the number of valence electrons, and the sum of their electronegativities are relevant to understanding bonding and molecular structure, the difference in electronegativities is the most critical factor in determining the nature of the bond between two specific atoms.