Atoms are everywhere. You’re made of atoms. Your dog is made of atoms. Your peanut butter sandwich? Yep. Made of atoms. Atoms are the smallest particle of matter. They’re so small that they can’t be cut, or divided. Molecules are made up of atoms. Confused? Think of a sentence. The words...

We know that all matter contains atoms, and those atoms contain protons, neutrons, and electrons. But atoms aren’t all the same. They have different amounts of protons, neutrons, and electrons. Scientists have discovered about 120 different types of atoms – or