1. CH 4 Earth Chemistry

2. Section 4.1 Matter is anything that takes up space and has mass.
An element is a substance that cannot be broken down into simpler, stable substances.
Most common elements in Earth’s crust:
Oxygen 46.6%
Silicon 27.7%
Aluminum 8.1%
Also Iron, Calcium, Sodium, Potassium, Magnesium, others

3. Isotopes
Atoms with the same number of protons and electrons, but different numbers of neutrons
Only Atomic Mass changes

4. Periodic Table Go to Pg 86 How is Atomic Mass Calculated?
Based on the isotopes that have different masses, the Periodic Table uses the average of the different masses for each element.

5. Practice Drawing Atoms
What does the atom of Oxygen look like?
What does the atom for Lithium look like?
What does the atom for Boron look like?

6. Why are the outer shell electrons important?
These are the electrons that are used for reactions! The outermost electrons are able to react with other atoms
Also Opposites attract
Let’s Identify the Valence Electrons for the groups of the Periodic Table

7. Ions Charged Atoms-Allow the atoms of the elements to react
Examples…….
Na+ + Cl-  NaCl
Al 3+ + O 2-  Al2O3
Opposites Attract!!!

8. Types of Bonds
Covalent Bonds-A bond that is formed by the attraction between atoms that share electrons.
Very strong Bond
Ionic Bonds- The attractive force between oppositely charged ions that results from the transfer of electrons from one atom to another
Very weak bond

9. Types of Bonds
Polar Covalent Bonds-In between an ionic and covalent bond- a Bond that does not equally share electrons and therefore creates a polar bond

10. Mixtures Elements and compounds are generally mixed together.
A mixture is a combination of two or more substances that are not chemically combined.
Heterogeneous Mixture- mixture that is not uniformly distributed.
Homogeneous Mixture- mixture that is uniformly distributed. IE a solution of Salt water.

11. Chapter 5 Minerals Know the four criteria for minerals.
Explain what a silicon-oxygen tetrahedron is and the different arrangements.
Know the seven properties of minerals that help us identify them and be able to explain how to find hardness.

12. Minerals
Examples
Rubies
Gold Nugget
Salt
A mineral is a natural, usually inorganic solid that has a characteristic chemical composition, an orderly internal structure, and a characteristic set of physical properties.

13. Minerals in Chihuahua

15. Characteristics of Minerals
Is it inorganic?
Not made out of previously living things
Does it occur naturally?
Things made in nature not a lab
Is it crystalline solid?
Has a regular repeating crystalline structure
Does it have a consistent chemical composition
A common chemical formula
Pg 103

16. Properties of a Mineral
Color
Streak
Luster
Cleavage and Fracture
Hardness
Crystal Shape
Density

17. Read pg
Create notes or an graphic organizer explaining in detail the 7 main properties of minerals.
For bonus you can take notes or continue your graphic organizer on the Special Properties of Minerals from page