Oxygen is in group 16 of the periodic table. An oxygen ion (O2-) has a charge of - 2. Which of the following would be most likely to combine with an oxygen ion to form a new compound?

A.

a calcium ion with a charge of + 2

B.

a fluoride ion with a charge of - 1

C.

a neon atom that has no charge

D.

a sulfide ion with a charge of - 2

A a calcium ion with a charge of + 2

Explanation:

Think of it this way:

every atom needs 8 electrons in the outer shell to be happy.

If an electron has a negative 2 charge that means that it needs 2 more electrons to be happy and calcium needs to lose to of its electrons to be happy. So calcium will happily give its two outer elctrons to oxygen.