Atoms have three components: protons and neutrons (the nucleus), and electrons.
The Nucleus
Can be found in the middle of the atom
Composed of protons and neutrons
Has overrall positive charge
Tiny compared to whole atom
Nucleus takes up the most mass of atom
Electrons
Negative charge
Tiny but take up most of the space
Are on shells around the nucleus
No mass
Atomic number is the number of electrons
Protons
Positive charge
Heavy
In the nucleus
Number of protons equals to number of electrons
Charge is same size as electron but opposite
Atomic number is the number of protons
Neutrons
No charge
Heavy
Found in nucleus
To find out how many neutrons there are you take away atomic number from atomic mass.
Atomic number
Unique to each element
Shows the number of electrons and protons
Atomic mass
The mass of atom
Number of protons and neutrons added together.
Electron Shells
First shell can only contain two electrons
Rest can contain up to 8 electrons
Also known as energy levels
Atom is happy when it has a full outer shell
If not it makes the atom want to react
Elements have only one type of atom.
Because each element has a unique atomic number that must mean each element have a unique amount of protons since the atomic number also tells how many protons and electrons there are.
