Which will form an ionic bond?

a. two oppositely-charged ions

b. any two neutral atoms

c. two oxygen atoms

d. two negative ions

A = Two oppositely charged ions.

Explanation:

ionic bond:

It is the bond which is formed by the transfer of electron from one atom to the atom of another element.  

Explanation:

Both bonded atoms have very large electronegativity difference. The atom with large electronegativity value accept the electron from other with smaller value of electronegativity. The one atom becomes anion and other c=becomes cation. Thus the bond formed between two opposite charged atoms is ionic bond.

For example:

Sodium chloride is ionic compound. The electronegativity of chlorine is 3.16 and for sodium is 0.93. There is large difference is present. That's why electron from sodium is transfer to the chlorine. Sodium becomes positive and chlorine becomes negative ion. The electrostatic forces are developed between oppositely charged atoms and bond is formed called ionic bond.

d.) the average kinetic energy of the gas particles is greater in container b because its particles move faster.

it is the most commonly accepted one