Answer
b.(magnesium and chlorine) and d.(potassium and sulfur) are likely to form an ionic compound
Work Step by Step
an ionic compound is formed by a metal and a nonmetal
a. helium is a noble gas (it is already stable) and oxygen is a nonmetal, they cannot form an ionic compound
b. magnesium is a metal and chlorine is a nonmetal, they can form an ionic compound
c.chlorine and bromine are both nonmetals, they cannot form an ionic compound
d.potassium is a metal and sulfur is a nonmetal, they can form an ionic compound
e. sodium and potassium are both metals, they cannot form an ionic compound
f. nitrogen and iodine are both nonmetals, they cannot form an ionic compound
