1. Earth’s Materials - Atoms, Elements, and Compounds

2. Structure of an Atom

3. Uniqueness of Elements An elements is defined by its Atomic Number (number of protons in the nucleus) i.e. Hydrogen’s Atomic Number is 1 Helium’s Atomic Number is 2 Mass Number (sum of protons and neutrons) i.e. Hydrogen’s Mass Number is 1 Helium’s Mass Number is 4

4. Periodic Table

5. Isotopes - elements with different numbers of neutrons in the nucleus. e N P N e Helium 3 ( 3 He) P e e P N P Helium 4 ( 4 He)

6. Ions - atoms with excess positive or negative charge (gain or loss of electrons from the outermost shell). Cations (positive charge, lose electrons) P e Hydrogen atom P e ElectronHydrogen ion ( H + ) + + Anions (negative charge, gain electrons)

7. Compounds - combination of atoms of one or more elements in a specific ratio. Examples: N 2 - nitrogen gas H 2 O - water CaCO 3 – calcite (a mineral) Ions dissolved in water will combine to form compounds

8. Types of Bonds Ionic - transfer of electrons between cations and anions. Moderate strength, Moderate hardness

10. Covalent - electrons are shared between atoms Types of Bonds Strong bond/ Hard mineral

11. Minerals

12. Questions -Which of the following are minerals? Explain! A.Ice (H 2 O) B.Water (H 2 O) C.Oil (C x H y O z ) D.Salt (NaCl) E.Synthetic (man-made) Diamond (C) It may be helpful to write out the definition of a mineral.

13. Five Requirements to Be a Mineral Naturally formed Solid Formed by inorganic processes Specific chemical composition Characteristic crystal structure

14. Properties of Minerals Crystal Form and Habit Cleavage Hardness Luster, Color, Streak Density Taste Feel Magnetism Reaction to Acid

15. Most Common Elements Oxygen Silicon Aluminum Iron Calcium Magnesium Sodium Potassium Percentage by Weight

16. Common Mineral Families OxidesO 2 Carbonates(CO 3 ) 2- Sulfates(SO 4 ) 2- SulfidesS Phosphates(PO 4 ) 3 Halides(NaCl-salt) Native Elements (Gold) Silicates(SiO 4 ) 4- Which mineral family would be the most common at the Earth’s surface?

17. Silicon-Oxygen Tetrahedron (SiO 4 ) -4 – anion Building Block of Silicates Combination of ionic and covalent bonds Combines with other tetrahedrons and/or cations

18. Mineral Formation Combination of Tetrahedron and cations form minerals i.e. Olivine

19. Silicate Structures Si:O 1:3 Si:O 1:2.75 Si:O 1:2.5

20. Silicon content increases with complexity of Structure 1:4 1:3 1:2.75 1:2.5 1:2 Silicon:Oxygen

21. Structure and Cleavage

23. Chemical Classification Ferromagnesium (Mafic) Silicates –Composed of Iron (Fe) and Magnesium (Mg) –Dark in Color Nonferromagnesium (Felsic) Silicates –Composed of Potassium (K), Sodium (Na), Calcium (Ca), etc. no Fe and Mg –Lower density –Light in Color Hornblende Orthoclase