1. How to Read the PERIODIC TABLE

2. The Periodic Table
An ELEMENT is a substance that cannot be broken down into simpler substances by chemical or physical means.
Is made of the same type of atoms.
Ex. Gold elements are made of gold atoms
Sometimes called a pure substance
Each element has their own little box on the periodic table with valuable information

3. ATOMIC NUMBER: Tells you how many protons are in the nucleus
SYMBOL: Abbreviated version of the element’s name.
(This may be ONE CAPITAL LETTER or ONE CAPITAL LETTER plus ONE LOWERCASE LETTER)
Sometimes the symbol matches the first one or two letters of the element’s name, other times it reflects the Latin name for the element
NAME: what the element is called.
ATOMIC MASS: This is the average mass of the atoms. It is found by finding the average of all the isotopes of an element.
Round to get your MASS NUMBER which is your # of protons + # of neutrons

4. information from the periodic table
Look at the atomic number in the box. It is two, meaning there are 2 protons in the nucleus of a Helium atom.
Now that we know the number of protons, we can say how many electrons we have. Electron number usually equals the proton number so there are 2 electrons.
Next look at the atomic mass. Round it to the nearest whole number. Write this number in the column for MASS NUMBER.
Now subtract your atomic number from your mass number to get the number of neutrons.
Name
Symbol
Atomic Mass
Mass number
Atomic number
# of protons
# of electrons
# of neutron
Helium He
4.0026 4 2

5. Try on your own Potassium 5 Ar 18 Gold K 39.1 39 19 19 19 20 Boron B
Name
Symbol
Atomic Mass
Mass number
Atomic number
# of protons
# of electrons
# of neutrons
Potassium 5 Ar 18
Gold K
39.1 39 19 19 19 20
Boron B
10.8 11 5 5 6
Argon 40 40 18 22 18 Au
197
118
197 79 79 79