1. Periodic Table

2. Periodic Table- An arrangement of elements in columns based on properties that repeat from row to row.
First organized by Dimitri Mendeleev, modeled after the card game solitaire
Elements were arranged into rows by increasing mass
Similar properties were placed in the same column

3. Today’s periodic table is arranged by atomic number
The atomic number increases as you move left to right
PERIOD - rows across
GROUP – columns up & down

4. Review - ELEMENTS
Can not be chemically broken down into simpler substances
Arranged into 3 groups on table:
metals, metalloids, non- metals
From left to right on the table elements become less like metals

5. METALS
good conductors of electricity and heat, usually solid at room temperature, malleable, reactive
Blue elements on YOUR table
TRANSITION METALS – special group of metals found in the middle section of the table, (groups 3-12)

6. METALLOIDS
Properties are in between the properties of metals and non- metals
All elements that share a border on the “Staircase” on your table

7. Non- Metals
Poor conductors. Can be solid liquid or gas at room temperature, not reactive
Red elements on YOUR table

8. Matter & The Atom

9. The term matter describes all of the physical substances around us
Matter is anything that has mass and takes up space
The Universe is made up of matter and energy

10. Matter is made up of atoms
*Matter is made up of atoms. *An atom is the smallest whole particle of matter. Atoms are the building blocks of matter. * Sub-Atomic particles are the tiny particles that make up an atom.

11. Atomic Structure NUCLEUS The center of the atom.
All the particles are inside or around the nucleus

12. Atomic Structure
proton (p+)
neutron (no)
electron (e-)

13. Atomic Structure Proton (p+) Located in the nucleus of the atom
Protons have a positive charge (+)
 Much larger and heavier than electrons
Number of protons is different for each element. If the number of protons changes, the element changes.

14. Atomic Structure Neutron (n0) Located in the nucleus of the atom
Neutral particle (has no electrical charge)
Largest particle, a bit bigger than a proton 

15. Atomic Structure Electron (e-) Found in a cloud outside the nucleus
Electrons have a negative charge (-)
Smallest particle
Orbit nucleus on energy levels

16. Atomic Number = number of protons in each atom of any element
All atoms want to balance their protons and electrons to be NEUTRAL (no electrical charge)
In a neutral atom, the # of protons = the # of electrons

17. Element
Atomic #
# protons
Hydrogen 1
Gold 79
Oxygen 8
Iron 26
Lead 82
Helium 2
Sodium 11
Sulfur 16

18. Atomic Mass– the sum of the mass of all the protons and neutrons in an atom
-- measured in Atomic Mass Units (amu)

19. Mass Number – sum of protons and neutrons in the nucleus
--can be used to find the number of neutrons in the nucleus
Mass # = atomic # + n or
n = mass # - p

20. 79 Au 197 the number of (p+) and (e-) (+) = (-) (MASS NUMBER)
ATOMIC NUMBER
the number of (p+) and (e-)
(+) = (-)
ATOMIC MASS
(MASS NUMBER)
PROTONS (+) + NEUTRONS (0)
PROTONS AND NEUTRONS = NUCLEUS 79 Au
197

21. Isotope – when an atom has a different number of neutrons than other atoms of the same element
Example: 2 Oxygen Atoms, one has 8 neutrons one has 9.

22. Isotopes The number of protons for a given atom never changes.
The number of neutrons can change. 
Two atoms with different numbers of neutrons are called isotopes
Isotopes have the same atomic #
Isotopes have different atomic Mass #’s

23. Electrons Electrons can be found in the electron cloud.
Energy Levels – electrons are located on these levels based on their energy

24. The lowest energy level is closest to the nucleus
--It holds 2 e-
The 2nd energy level holds 8 e-
The 3rd energy level holds 8 e-
ELECTRONS FILL THE LEVELS FROM INSIDE OUT.

25. Electrons can change levels when energy is added to or removed from the atom
If an e- gains energy it is in “excited state” and moves out an energy level
If it loses energy it goes in an energy level

26. Valence Electrons - Number of electrons in outside row
Identified with a Roman numeral number at the top of each group
All elements in each group have the same number
Column VIII (group 18) has 2, 8 or 18 – it is FILLED!
Transition metals have no specific roman numeral

27. PT COMMANDMENTS
For atoms and elements

28. All atoms want to fill their outer energy level.1.
All atoms want to fill their outer energy level.

29. 2.
The roman numeral columns tell you how many electrons an atom has currently in its outside level.

30. 3.
THE SUBATOMIC PARTICLES ARE:
ELECTRONS (-) NEGATIVE electrical charge
PROTONS (+) POSITIVE electrical charge
NEUTRONS (0) NO electrical charge

31. 4.
Protons have a mass of 1 atomic mass unit (AMU)
Electrons have almost zero mass (0 amu).

32. Au (the number of (p+) and (e-) ) 197 (+) = (-)5.
ATOMIC NUMBER
Au (the number of (p+) and (e-) )
197 (+) = (-)
6. ATOMIC MASS
PROTONS (+) + NEUTRONS (0)
**don’t forget, protons and neutrons are in the nucleus!

33. maximum number of
2 electrons
electrons in
each orbit
8 electrons
18 electrons
Nucleus
p+ and n0