Organization of the Periodic Table

Atomic Number

-the number of protons in the nucleus
-tells us the identity of the element

Isotopes

-atoms with the same number of protons but different numbers on neutrons
-Example: Carbon
.Carbon-11
6 protons
5 neutrons
unstable

.Carbon-12
6 protons
6 neutrons
stable

.Carbon-13
6 protons
7 neutrons
stable

.Carbon-14
6 protons
8 neutrons
unstable

Magnets

Facts:

.Magnets have been known for centuries
.Ancient Greeks used a stone substance called "magnetite"
-discovered this stone always pointed in the same direction
."lodestones" or magnets were used in navigation
.William Gilbert, English Physician-1600-Discovered Earth is a magnet
-Earth has magnetic poles

Magnetism
-the force of attraction or repulsion of a magnetic material due to the arrangement of it atoms, particularly its electrons.
-The ends of the magnet is where the magnetic effect is the strongest
-called "poles"-each magnet has 2 poles [North & South]

Magnetic Fields

-The region where the magnetic forces act is called the "magnetic fields"

How to Demagnetize a Magnet:

1.Drop it
2.Heat it

.Atoms themselves have magnetic properties due to the spin of the atom's electrons.
.Groups of atoms join so that their magnetic fields are all going in the same direction
-these area of atoms are called "domains"

unmagnetized-randomized domains
magnetized-aligned domains

The Earth is a Magnet

-exerts magnetic forces and is surrounded by a magnetic field that is strongest neat the North and South magnetic poles
-needle of compass always points toward the magnetic south pole "North"
*Remember Opposites Attract*