1. An atom is… The smallest unit of _____________. So what is that? Anything that has ____________ and takes up _____________ is matter! Everything is made up of ________________; even you!

2. An Atom is made of… ________________ – negatively charged particles that orbit the nucleus (center). __________________ – particles that are neutral or have no charge. These are inside the nucleus. ________________ – positively charged particles inside the nucleus Protons in the atom’s nucleus attract the electrons and keep them in orbit around the nucleus.

3. Atoms are small Atoms are so small that they cannot be ______________with regular microscopes. There are special microscopes that can give you a feel of what atoms look like. The number of protons in an atom determine what type of ________________ it is. This is called the Atomic Number. So that means all the elements on the Periodic Table are different types of atoms (with different numbers of protons and electrons).

4. A molecule is made of at least two atoms. Water molecule A ________________ is a molecule that contains two different types of atoms (elements). NOT ALL Molecules are __________________