Question

an atom will form a chemical bond with another atom if 1. ions can be formed. 2. the resulting molecule is more stable. 3. the other atom is identical to it. 4. their outer energy levels are already filled.

Explanation:

Atoms form chemical bonds to achieve a more stable state, usually to fill their outer - energy levels. A more stable molecule is the driving force for bond formation. Just the formation of ions is not the sole reason for bonding. Atoms don't need to be identical to bond, and atoms with filled outer - energy levels are generally unreactive and less likely to form bonds.

Answer:

1. the resulting molecule is more stable.