What is a simple molecule?

A simple molecule is a molecule made up of two atoms that are held together by covalent bonds. Hydrogen, Oxygen, Water, and Carbon Dioxide are some of the most common examples of simple molecules. A Hydrogen molecule (H2) is made up of two hydrogen atoms (H) that are covalently bonded. An Oxygen molecule (O2) is made up of two oxygen atoms (O) that are covalently bonded. A Water molecule (H2O) is made up of 2 hydrogen atoms (2H) and 1 oxygen (O) atom, which are covalently bonded. A Carbon dioxide molecule (CO2) is made up of one carbon atom (C) and 2 oxygen atoms (2O), which are covalently bonded.