1. Let’s Review the STRUCTURE OF AN ATOM

2. Nucleus Proton Neutron Electron Valence electron Shells
Let’s review the parts of an atom, then we will draw and label our own!
Before we continue, in 1 minute, write down everything you can remember about the following items.
Nucleus
Proton
Neutron
Electron
Valence electron
Shells

3. WHAT IS THE NUCLEUS? The central (middle) part of an atom.
Composed of protons and neutrons.
Contains most of an atom's mass.

4. WHAT IS A PROTON? Positively charged particle.
Found within an atomic nucleus.
Same as the ATOMIC NUMBER

5. WHAT IS A NEUTRON? Uncharged (neutral) particle.
Found within an atomic nucleus.

6. WHAT IS AN ELECTRON? Negatively charged particle.
Located in shells that surround an atom's nucleus.
Much smaller than protons and neutrons

7. What is the Shell? - Where the electrons are located.
Also known as energy levels and electron cloud.
(FYI) The PERIODS on the Table of Elements tells you how many shells an atom has.

8. Energy level Max# of electrons 1 2 8 3 18 4 32
Electrons Per Energy Level Chart
Energy level
Max# of electrons 1 2 8 3 18 4 32

9. Valence Electron Only the electrons in the OUTER MOST SHELL
Valence electrons are what bond with other atoms
(FYI) The GROUPS on the periodic table tell you how many valence electrons they have. Ex: If they are in group 1, they have 1 valence electron.

10. Now let’s draw an atom for the element Neon.
1. Draw the number of protons
2. Draw the first shell. How many electrons can you put on the first shell? Draw them (remember that they are smaller than protons). (2)
3. Draw 2nd shell. How many electrons do you have left and how many can go on the 2nd shell? Draw them. (8)
4. Solve for neutrons. (Remember the word “MAN” Mass - Atomic number = Neutrons. Draw them.
Label the protons, neutrons, nucleus, electrons, valence electrons, and the electron cloud.
Now let’s draw an atom for the element Neon.

11. Check Your Work
valence
Electron
Cloud
Nucleus