1. Chapter 2: Matter and Minerals

2. What is Matter?
Matter – the substance of which any physical object is composed
States of Matter:
Solid
Liquid
Gas
Controlling factors:
Temperature
Pressure
Examples: Gold Mercury Oxygen
solid
liquid
gas

3. The stuff that makes up all matter
The make-up of solid matter on Earth:
Atoms    
(smallest) (largest)
Elements
Compounds
Minerals
Rocks
Atoms:
the stuff that builds elements
the smallest particle that uniquely defines an element

4. Atomic Structure Particles that make up an atom:
Protons: positive (+) charge
Neutrons: no charge
Electrons: negative (-) charge
Protons + neutrons define the nucleus of an atom.
Layers of electrons that orbit around the nucleus are called orbitals or energy-level shells.

5. Atomic Structure

6. The stuff that makes up all matter
The make-up of solid matter on Earth:
Atoms  Elements  Compounds  Minerals  Rocks
(smallest) (largest)
Elements:
fundamental building blocks
smallest matter that can’t be broken down

7. Periodic Table of Elements

8. Periodic Table of Elements
Atomic Number: (# of protons)
Atomic Weight = # protons + # neutrons
Atomic number = # protons
These are called isotopes.
Example: (Carbon) 12C 13C 14C
Can atoms of the same element have different mass numbers?
Yes

9. Periodic Table of Elements
Isotopes: are atoms of the same element with
different mass numbers, the number of
neutrons changes.
Atomic Weight = # protons + # neutrons
Atomic number = # protons
These are called isotopes.
Example: (Carbon) 12C 13C 14C
Can atoms of the same element have different mass numbers?
Yes

10. Modeling Atoms Electrons and Their Energy Levels
Some Rules to Remember
about atoms and their e-
A: The inner or first energy
shell fills with e- first.
B: The 1st energy shell can
hole 2e- but no more than 2e-.
C: The 2nd energy shell can hold up to 8e-
but no more than 8e-.
D: the 3rd energy shell can hole up to 18e-
but no more than 18e-.

11. E: The 4th energy shell
can hold 32e-.
F: the 5th energy shell
can hole 50e-.
If there are more e- that the energy shell can hole, they “spill” into the next level or shell.

12. Modeling Atoms
The octet rule: says that atoms tend to gain, lose or share electrons so as to have eight electrons in their outer electron shell.
The bonding in carbon dioxide (CO2)- all atoms are surrounded by 8 electrons, according to the octet rule. CO2 is thus a stable molecule.

13. Valence Electrons
Electrons in the outermost shell of an atom are called valence electrons; they dictate the nature of the chemical reactions of the atom and largely determine the electrical nature of solid matter.
Valence Electrons participate in the formation of a chemical bond;

15. Modeling Atoms

17. Atomic Structure Atoms of the same element:
have the same number of protons (i.e., same atomic number)
can have different numbers of neutrons (referred to as isotopes)
can have different numbers of electrons
Ion – an atom that has gained or lost an electron

18. Atomic Structure Types of IONS:
CATIONS – a loss of electrons, resulting in a positive (+) charge
ANIONS – a gain of electrons, resulting in a negative (-) charge
Examples: Na+ (cation) Cl – (anion)
NaCl (table salt)
chemical compound

19. Atomic Structure Sodium atom Chlorine atom loses an electron
(becomes positively
charged)
Chlorine atom
gains an electron
(becomes negatively
charged)

20. Compounds Examples: NaCl H2O
Atoms  Elements  Compounds  Minerals  Rocks
(smallest) (largest)
Definition:
A chemical compound consists of elements that combine in a specific ratio.
Examples: NaCl H2O
The smallest quantity of a compound is called a molecule.
Molecules are held together by chemical bonding.

21. Bonding – chemical matrimony
Chemical bonding:
formation of a compound by combining two or more elements
manner in which electrons are distributed among atoms (valence electrons)
In bonded atoms, electrons may be lost, gained, or shared.
4 types of bonding:
ionic covalent metallic van der Waals

23. Bonding – chemical matrimony
Ionic bonding:
electrons are transferred between atoms forming attracting ions (e.g., NaCl)
Na+
Cl–

24. Bonding – chemical matrimony
1. Ionic bonding:
orderly arrangement of oppositely charged ions
bonds are moderately strong (salt dissolves in water)

25. Periodic Table of Elements

26. Bonding – chemical matrimony
2. Covalent bonding:
electrons are shared between atoms
generally strong
bonds
(e.g., diamond, pure C)
Chlorine gas molecule, Cl2

27. Bonding – chemical matrimony
3. Metallic bonding:
electrons drift around from atom to atom (e.g., copper, gold, silver)
good conductors of electrical current
generally weaker, less
common than other bonds
This is the world's largest
Gold Nugget ever found.
Discovered in 1872 and is
called the Holtermann Nugget.
It was 630lbs in weight.
Gold, Au

28. Bonding – chemical matrimony
4. Van der Waals bonding:
sheets of covalently bonded atoms held together by weak electrostatic forces
very weak bonds
examples: graphite, mica

29. What kind of bonding do you prefer?
In a covalent world…
In an ionic world…

30. Compounds (Minerals, Organic Compounds)
Atomic Particles
Atoms (Elements)
Compounds (Minerals, Organic Compounds)
Rocks
Living Things
Earth
Biosphere

31. The stuff that makes up all matter
The make-up of solid matter on Earth:
Atoms  Elements  Compounds  Minerals  Rocks
(smallest) (largest)

32. Minerals: the building blocks of rocks
Definition of a Mineral:
naturally occurring
inorganic
solid
characteristic crystalline structure
definite chemical composition
Definition of a Rock:
A solid aggregate (mixture) of minerals

34. Mineral characteristics
Definition of a Mineral:
naturally occurring
inorganic
solid
characteristic crystalline structure
definite chemical composition
steel plastic sugar table salt mercury ice coal
no, #1
no, #1
no, #1,2
YES!
no, #3
YES!
no, #2
basalt obsidian mica gold paper chalk coral
no, #5
no, #4
YES!
YES!
no, #1,2
no, #2
no, #2

35. Mineral characteristics
Naturally formed
No substance created artificially is a mineral.
examples: plastic, steel, sugar, paper
Inorganic
Anything formed by a living organism and containing organic materials is not a mineral.
examples: wood, plants, shells, coal
Solid
Liquids and gases are not minerals.
examples: water, petroleum, lava, oxygen

36. Mineral characteristics
Characteristic crystalline structure
must have an ordered arrangement of atoms
displays repetitive geometric patterns in 3-D
glass not a mineral (no internal crystalline structure)
Definite chemical composition
must have consistent chemical formula
examples: gold (Au), quartz (SiO2), orthoclase (KAlSi3O8)
basalt (like many other rocks) contains variable ratios of different minerals; thus, has no consistent formula

37. How many minerals are there?
Nearly 4,000 types of minerals
Only ~30 occur commonly (whew!)
Why not more?
Some combinations are chemically impossible
Relative abundances of elements don’t allow more

38. Element abundances in the crust
All others: 1.5%