1. Earth Chemistry
Chapter 8

2. Matter
8.1
What is Matter?

3. What is Matter? Matter takes up space and has mass.
Mass is the amount of matter in an object
Different types of matter have different Physical and Chemical Properties.

4. Physical and Chemical Properties
Physical Properties
Characteristics that cam be observed without changing composition
Examples
Density
Color
Boiling Point
Conductivity
Chemical Properties
Substances interact to form different types of matter
Examples
Corrosive
Acid/Base
Combustible
Oxidizer

5. Atoms and Elements Matter is made of elements.
Substances that have chemical and physical properties
>90 natural elements
Only 8 elements make up 98% of Earth’s crust
O, Si, Al, Fe, Ca, Na, K, Mg.
Atoms are the smallest unit of an element that still retain properties.
Cannot be broken down smaller
1 million atoms side by side make the thickness of a piece of paper

6. Subatomic Particles Protons and Neutrons are found in the nucleus
Proton (+), Neutron (neutral)
Electrons surround the nucleus in the electron cloud.
Electron (-)

7. Elements are arranged according to properties (NOVA Elements – Periodic Table)

9. Periodic Table Arranged by Properties of metals
Atomic number
Properties of the elements
Properties of metals
Malleable, good conductors, high MP, luster, ductile, give up electrons easily.
Properties of non metals
Not good conductors, brittle, low MP.
Do not give up electrons easily

10. Metaloids Have properties of both metals and non metals.
Found along the stair step line on the periodic table.

11. Periodic Table Atomic Number Mass number Number of Protons
Number of Electrons
Mass number
Protons + Neutrons
Amu - atomic mass unit.

12. Quiz Which letter is the atomic mass?B
Which letter is the element’s atomic number? A

13. Quiz Carbon has how many protons? 14 is Silicon’s _____.6
14 is Silicon’s _____.
Atomic Number
How much mass does one oxygen atom have?
amu

14. Quiz How many electrons does potassium have?
19 = atomic number
How many neutrons does potassium have?
39-19=20

15. NOVA Elements Elemental Earth

16. Isotopes
Atoms of the same element that differ from each other their mass number.
Same number of protons, different number of neutrons.
Hydrogen, Deuterium, Tritium.

17. Isotopes Movie

18. Combinations of Atoms
8.2

19. Compounds 2 or more elements chemically combined
Creates a new substance with properties that differ from the original elements.
NaCl, H2O, CaCO3
Combining Elements

20. Energy Levels An electron can only occupy 1 energy level at a time.
An atom can contain many energy levels.
Energy levels can only hold a max number of electrons.
2n2 ; n=energy level

21. How many electrons can the 1st energy level hold?
2(1)2 = 2

22. How many electrons can energy level 2 hold?
2(2)2 = 8

23. How many electrons can energy level number 3 hold?
2(3)2 = 18

24. Bohr Model Shows protons and neutrons in the nucleus.
Electrons in energy levels around nucleus.
How they form compounds is based on their electron arrangement.

25. Bohr Model Different elements have different # of energy levels
Period
Valence electrons are the electrons in the outer most energy level
Happy with eight

26. Period = # of energy levels Group = Valence electrons

27. Electron Dot Diagram
A shorthand notation to show the number of valence electrons in an atom.
Easier then Bhor diagrams
Also called Lewis Symbols

28. Which is the correct dot diagram for Neon?

29. Which is the correct dot diagram for chlorine?

30. Chemical Bonds Produced by the interactions of electrons
Interactions based on outer shell electrons
Form bonds by sharing or transferring electrons.

31. Ionic Bonds Transfer of electrons
Bond between a metal and non metal element
Ions combine to form ionic bond
Forms a strong bond

32. Ionic Bond Movie

33. Covalent Bonds Atoms share electrons to form chemical bonds.
Forms a weaker bond.

34. Covalent Bond Movie

35. Chemical Formulas Represents the elements a compound contains
Indicates the relative number of atoms in each element
Numbers are represented by subscript.

36. What elements are present in this compound?
H= Hydrogen O = Oxygen

37. How many atoms of each element are there in water?
Hydrogen = 2 Oxygen = 1

38. What elements are present in this compound?
Na = Sodium O=Oxygen H=Hydrogen

39. How many atoms of each element are there in Sodium Hydroxide?
Sodium = 1 Oxygen = 1 Hydrogen = 1

40. What elements are present in this compound?
Ca=Calcium P=Phosphorus O=Oxygen

41. How many atoms of each element are there in Calcium Phosphate?
This one is tricky!
Calcium=3 Phosphorus=2 Oxygen=8

42. Mixtures
Material that contains two or move substances that are not chemically combined.
Substances keep their individual properties.
Can be separated by physical means
Rocks, soil, air, smog

43. Solution
Mixture in which one substance is uniformly dispersed in another.
Salt water
Alloy
A solution of two or more metals.
Structure of an Alloy