Multiple choice

The formula of calcium oxide is

  1. CaO2

  2. CaO

  3. CaO3

  4. CI

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Calcium oxide has the chemical formula CaO. Calcium has a +2 charge and oxygen has a -2 charge, so they combine in a 1:1 ratio to form a neutral compound.