Atoms

Rutherford

BOHR MODEL: The structure of an atom.

Atomic Mass= Protons + Neutrons

Nucleus Charge is Positive

Positive Protons +

Neutral Neutrons 0

Negative Electrons -

P rotons (positive)

E lectrons (negative)

N eutrons (neutrons)

Ve Valence Electrons

Periodic Table Groups- similar properties of element

Groups = Valence Electrons (1A, 2A, 3A, 4A, 5A, 6A, 7A, 8A)

Valence Electrons= Reactivity

Period- # of energy levels are

in an atom.

Chemical Equations

Law of Conservation of Mass- Total of atoms on the reactants must equal the product

2Na + 2H20 => 2NaOH + H2

REACTANTS PRODUCTS

YIELDSIGN

Reactants are to the left of the yield sign

Products are to the right of the yield sign

Counting Atoms

Coefficient- the # of molecules

# of atoms of each element

If no subscript, there is at least 1

atom of that element

Ca - 1 x 2 = 2 atomsC- 1 x 2 = 2 atomsO- 3 x 2 = 6 atomsTotal = 10 atoms

Chemical Changes NEW SUBSTANCE CREATED

Physical Changes

MORE MASS

MORE INERTIA

LESS MASSLESS INERTIA

Newton’s Third LawEXAMPLE...

FOR EVERY ACTION….

THERE IS AN EQUAL AND OPPOSITE REACTION...

FORMULA FOR SPEED/DISTANCE/TIME