1. Periodic Table and Elements

2. Elements
Elements:
A substance that cannot be broken down into a simpler substance by chemical means…
Building block of all matter
NOT man made, comes from the Earth

4. Periodic Table of Elements
Groups
Columns
Same number of electrons in the outer shell
First element in each group is the family name
Ex: Group 15 (XV) is the nitrogen family
Periods
Rows
Same number of atomic orbitals
Each element in a column and row has characteristics that place it in that column and row

5. Periodic Table of Elements
Element Name
Symbol
Letters that represent an element
Atomic Number
Atomic weight
Name
Atomic Weight (mass)
Iron 26 Fe
55.845

6. The Atom Elements are made of atoms
An atom is the smallest part an element can be broken down into and still keep the characteristics of that element.
All atoms of an element are the same…
BUT, atoms of different elements are NOT the same

7. The Atom The atom had three main parts Proton Neutron
Positive (+), found inside the nucleus, has weight
Same number as the atomic number
Neutron
Neutral, found inside the nucleus, has weight
The number of neutrons is found by subtracting the atomic # from the atomic weight
(atomic weight – atomic #)

8. The Atom Atomic Weight Atomic Number Electron
Negative (-), found outside the nucleus on rings or orbits, spinning around the nucleus, does not have weight.
Same number as the atomic number
Atomic Weight
# of protons + # of Neutrons
Atomic Number
Represents the number of protons and/or electrons in an atom

9. The Atom Orbital Also called a shell
Outside the nucleus where electrons are found racing around

10. The Atom - - - - - - - - - - Electron Configuration
Rule:
Neon:
10 protons
10 neutrons
10 electrons - - - -
P: 10
N: 10 - - - - - -

11. Molecules/Compounds A molecule: A compound:
is a stable, electrically neutral arrangement of atoms.
Has 2 or more atoms held together by bonds.
A compound:
is a molecule with 2 or more different elements.
All compounds are molecules, but not all molecules are compounds.

12. Molecules/Compounds Is water, H2O, a molecule or a compound?
It’s both. Since water is a compound, it has 2 elements, it is automatically a molecule.
How many atoms are held together in a water molecule, H2O?
3 atoms
How many elements are in a water molecule, H2O?
2 elements