Parts on an atom

1. The parts of an Atom

2. The atom
An Atom: The most basic unit of
matter.
An atom has a dense nucleus and a
cloud of negatively charged electrons
around it.
If matter is what everything is made of, and
matter is made of atoms…
Then, everything is really made of atoms!

3. An Electron
Electron: A subatomic particle with a
negative electrical charge.
An electron’s mass is so small that it is
generally not even considered.

4. A Nucleus
Nucleus: The dense center of an atom
containing protons and neutrons.
Nucleus

5. A Proton
A Proton: A subatomic particle within
the nucleus of an atom that has a
positive charge.

6. Neutron
A Neutron: A subatomic particle within
the nucleus of an atom that has a
neutral charge.

7. Energy Level
The energy level of an atom is as
follows:
2,8,8
The first shell has two electrons
The second shell has 8 electrons
The third shell has 8 electrons
MEMORIZE: 2,8,8!!!!!!!!!!

8. Atomic Number
The atomic number is
the number mainly
associated with the
element and represents
the number of protons
present in the atom.

9. Mass Number
The total number of
protons and neutrons.
The mass of an atom
comes from the protons
and neutrons.
Therefore, the mass
includes the masses of
each added together.
This number can be found
at the bottom, typically.
Mass Number

10. Atomic Mass
Sub atomic particles are measured in
AMU’s. AMU stands for Atomic Mass
Unit.
Every proton has a mass of 1 AMU
Every Neutron has a mass of 1 AMU
Remember, electrons don’t have a
measureable mass.

11. Element
A pure chemical substance consisting
of ONE type of atom.