Fox was uncharacteristically quiet as he drove, and if it werenât for his occasional turning of the steering wheel, I would have thought someone had crafted a wax-statue of him and stuck it next to me. âThanks for driving me,â I finally said, just to say something.
Everything is made of atoms. An atom is the smallest particle of an element, like oxygen or hydrogen. Atoms join together to form molecules. A water molecule has three atoms: two hydrogen (H) atoms and one oxygen (O) atom. That's why water is sometimes referred to as H2O. A single drop of water contains billions of water molecules.
A molecule is what you get when any atoms join together. A compound is what you get when atoms of two or more different elements join together. All compounds are molecules, but not all molecules are compounds. Water is a molecule because it is made from atoms that have been chemically combined. It is also a compound because the atoms that make water are not all the same-some are oxygen and some are hydrogen. Oxygen in the atmosphere is a molecule because it is made from two atoms of oxygen. It is not a compound because it is made from atoms of only one element-oxygen. This type of molecule is called a diatomic molecule, a molecule made from two atoms of the same type.