.When sodium atoms (Na) and chlorine atoms (Cl) join to make sodium chloride, or table salt, they form an ionic bond. Using this information, which pair of elements is most likely to form an ionic bond? potassium (K) and fluorine (F)
aluminum (Al) and aluminum (Al)
sulfur (S) and oxygen (O)
calcium (Ca) and neon (Ne)

potassium (K) and fluorine (F)

Explanation:

Potassium is an alkali metal just like sodium and fluorine is a halogen just like chlorine. A metal and nonmetal will often join to form an ionic compound.

Aluminum, if it was going to bond to itself, would be a metallic bond.

Sulfur and oxygen are both nonmetals and would form a covalent bond.

Calcium would not bond with neon as neon is a noble gas.