which pair of elements will form an ionic bond?\no n and o\no k and br\no c and cl\no fe and ni

Explanation:

Step1: Recall ionic - bond concept

Ionic bonds form between a metal and a non - metal.

Step2: Analyze each pair

• N (nitrogen) and O (oxygen) are both non - metals. They form covalent bonds.
• K (potassium) is a metal and Br (bromine) is a non - metal. They can form an ionic bond.
• C (carbon) and Cl (chlorine) are non - metals. They form covalent bonds.
• Fe (iron) and Ni (nickel) are both metals. They do not form ionic bonds.

Answer:

K and Br