1. Review PowerPoint
Units 1 and 2

2. Atoms Atoms are the basic particle from which all elements are made
Atoms make up everything, your body, the air, the ground
An element, is one or more atoms that cannot be chemically broken down into simpler substances

3. The Periodic Table
All of the elements that have been discovered are found on the periodic table of elements
Remember the periodic table of elements was first developed by Dimitri Mendeleev
The current periodic table is arranged by increasing atomic number

4. Atoms are made up of three parts
Subatomic particles – are the tiny parts that make up atoms, there are three: protons, neutrons, and electrons
What you need to know…
Location – 1. Nucleus 2. electron cloud
Charge – positive, negative, neutral
Mass – 1 AMU OR much smaller than that

5. Protons
Super Important!!! Because, they tell you what type of element it is.
Protons never change – Every atom of one element, ALWAYS have the same number of protons
Carbon has 6, Helium has 2, Lithium has 3
Positive, in the nucleus, 1 AMU

6. Electrons
In a neutral atom, the number of electrons is the same as protons
The electron cloud is the entire area where electrons might be found
Valence electrons are the electrons in the outside energy shell = chemical properties
Negative, electron cloud, 1/2000 AMU

7. Neutrons Do Nothing!!!!! They just add to the mass
Isotopes are atoms of the same element with different numbers of neutrons
On the STAAR – They will try to trick you about neutrons
The number of neutrons in an atom is figured out by taking the atomic mass (Labeled) and subtracting the atomic number (Labeled)
On the STAAR – they will give you the mass, and the atomic number (number of protons) – use what you are given!!!
Nucleus – Neutral – 1 AMU

8. THE PERIODIC TABLE IS A MAP
How to remember the difference between horizontal and vertical
Groups – vertical lines in the periodic table – groUP
Periods – horizontal lines in the periodic table
Periods are at the end of sentences………. Sentences run from left to right

9. groUPs
The groups of the periodic table, have elements with the same chemical properties
They all have the same number of valence electrons
The empty spaces are there so the elements with similar numbers of VE- can stay in the same group

10. Numbers of VE- Group 1 = 1 Group 2 = 2 Groups 3-12 are crazy = 1 OR 2

11. 8 is GREAT!!! All atoms want a full outside shell of electrons
8 makes a full outside shell
This is why the group 18 elements – the Noble Gasses – don’t react
All other elements want to gain or lose electrons to get a full outside shell

12. Drawing atoms based on element tags
Remember the atomic number tells you how many protons and electrons to draw
The atomic mass – the atomic number tells you how many neutrons to draw

13. Draw this atom

14. Draw this Atom

15. Draw this atom

16. Draw this atom

17. Draw this atom