Parts of the atom

1. PROTON (p+) → POSITIVE charged particle, found in the NUCLEUS, that makes up at least HALF of the MASS of an atom!

The number of p+ determines the TYPE of atom (they DON’T change)!

2. NEUTRON (n0) → NEUTRAL particle, found in the NUCLEUS, that makes up the rest of the mass of an atom.

The number of n0 can CHANGE → ISOTOPE

Act as the “glue” to keep the protons together (Nuclear force)

3. ELECTRON (e-) → NEGATIVE particle, found in the CLOUD, that has almost NO mass.

The number of e- can CHANGE → makes charged atoms (IONS)

Electrons exist in ENERGY LEVELS, have energy, and are responsible for CONNECTING atoms together (BOND)

Periodic Table contains boxes with information:

1. ATOMIC NUMBER:  tells you the number of PROTONS in an atom!

Tells you:  Number of p+ AND the number of e-  (IF the atom isn’t charged)

II Mass Number:  the total number of protons and neutrons in an atom (p+  +   n0)

Used to find the number of NEUTRONS → SUBTRACT mass number and atomic number!

Mass number  - Atomic Number = n0 

Remember → this CAN CHANGE (isotopes)