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 in the sentence are like molecules. The letters in the words are atoms. They’re the smallest part of the sentence, but they’re very important. When they combine, they make words, which make sentences.

- In the middle of an atom is the nucleus. The nucleus contains protons, which have a positive electrical charge, and neutrons, which have no charge.
- Electrons circle around the nucleus and have a negative electrical charge. Their total negative electrical charge is equal to the protons’ positive electrical charge.
- Atoms always have the same number of electrons, protons, and neutrons. The positive electrical charge of the protons attracts the electrons to it.
- Atoms bond with each other to make molecules.
Vocabulary
- Atom: The smallest particle of matter. The word atom comes from the Greek language and means “indivisible,” or cannot be divided.
- Bond: join, stick to
- Nucleus: the center of an atom
Q and A
Question: Do atoms contain elements?
Answer: No, but elements contain atoms. Atoms are the smallest building block of matter.
Learn More
Watch an animated video explaining atoms, molecules, protons, electrons, and neutrons.
Still confused? Here’s another video from Scholastic.