1. Atoms and the Periodic Table

2. Atomic Structure Based on the current Electron Cloud Model
Neutron
Found in the nucleus
Has no charge
Mass is 1 amu
Nucleus
Contains protons and neutrons
Has an overall positive charge
Contains most of atom’s mass
Proton
Found in the nucleus
Has a positive charge
Mass is 1 amu
Electron
Found outside of the nucleus in the electron cloud, arranged in energy levels (shells)
Has a negative charge
Electron Cloud is mostly empty space and determines the size of the atom.

3. Development of the Periodic Table
Russian scientist who created a periodic table which organized elements by atomic weight (mass) and similar properties.

4. What is an element?
Basic substance on Earth that cannot be broken down into any other substance.
Represented by a symbol (capital letter or capital and lowercase letters)
Example: O (oxygen)
Au (gold)

5. What is a compound?

6. Element or Compound?

7. Element or Compound? Compound Hydrogen, Sulfur, Oxygen Element Helium
Chromium, Nitrogen, Hydrogen, Oxygen
Compound
Magnesium, Nitrogen, Oxygen
Compound
Barium, Phosphorus, Oxygen
Element
Oxygen
Compound
Hydrogen, Phosphorus, Oxygen
Compound
Zinc, Oxygen, Hydrogen
Element
Carbon

8. Common Household Compounds
CaCO3
NaHCO3
NaClO
NaCl
NH3
C9H8O3

9. Periodic Table of Elements

10. Groups or Families
Periods 18
7 periods
Elements within the same period have the same number of energy levels or electron shells.
They have the same number of valance electrons and have similar properties.
Groups 1 and 17 are highly reactive because they want to either give or receive 1 valance electron

11. Using the Periodic Table
Atomic Number – tells us the number of protons and electrons
Element Symbol
Atomic Mass – tells us the total number of protons and neutrons
Element Name

12. Using the Periodic Table
tomic Number
ass
rotons
tomic Number
lectrons
eutrons

13. Practice

14. Practice Answers

15. The Atoms Family Math Challenge
Atoms Family Song

16. Understanding Chemical Formulas
What is a chemical formula?
Chemical formulas are a way to show which elements and how many atoms of each element are in a compound.

17. Chemical Formula Example

18. Counting Atoms be

19. Counting Atoms Practice
1 1
5 2
6 1
8 3
10 3
6 3
9 3
13 3

20. Chemical Equations
A chemical equation is a written representation of the process that occurs in a chemical reaction.
A chemical equation is written with the reactants on the left side of an arrow and the products of the chemical reaction on the right side of the equation.

21. Chemical Equations

22. Balancing Chemical Equations
The Law of the Conservation of Mass says that every atom that “goes into” a chemical reaction must “come out of” the chemical reaction.
To balance a chemical equation you must have the same number of atoms on each side.
2H2 + O2 2H2O
So count the atoms for each side:
H – 4
O - 2
H – 4
O - 2

23. Balanced or Unbalanced?
Determine whether or not the equation is balanced or not.
Write a “B” for Balanced and a “U” for Unbalanced B B B B U B B