1. ATOMS AND ATOMIC STRUCTURE

2. WHAT IS AN ATOM? The smallest unit of an element.
Consists of a central nucleus surrounded by one or more electrons.

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

4. Positively charged particle.
Found within an atomic nucleus.
PROTON

5. Neutral particle.
Found within an atomic nucleus.
NEUTRON

6. ELECTRON Negatively charged particle.
Located in shells that surround an atom's nucleus.
ELECTRON

7. ELECTRON CLOUD The area surrounding the nucleus of an atom.
Electrons are found here.
Most of the volume of the atom in the electron cloud.
ELECTRON CLOUD

8. PROTONS = ELECTRONS In stable atoms…
The ATOMIC NUMBER tells you the number of PROTONS in an atom (and ELECTRONS)

9. To find the number of protons, look at the atomic number (top number).

10. To find the total number of protons and neutrons, look at the atomic mass (bottom number).

11. To find the number of neutrons only, you subtract the atomic number (top number) from the atomic mass (bottom number).
Round mass to the nearest whole number, then subtract.