1. Chapter 3: Earth’s Environmental Systems
Matter and the Environment

2. How do the nonliving parts (abiotic factors) of Earth’s systems provide the basic materials to support life?
Gulf’s “Dead Zone”
Bottom waters of the dead zone indicate hypoxia (low oxygen levels)
Normal water: 10ppm
Hypoxic water: below 2ppm
Appears each spring and grows until fall
Why?

3. Why is chemistry sooooo important?
How pollutants cause acid rain?
How greenhouse gases contribute to global warming?
How pesticides and other chemicals such as plastics or hormones affect our health and the health of wildlife and the environment?
Clean-up and disposal of hazardous waste
Bioremediation…using living organisms to consume or neutralize polluting substances

4. Elements
Has mass and
occupies space
Fixed Composition
Variable Composition
Made of 2
or more atoms
Covalent
Substances can
Be easily distinguished
Ionic
One type
Of atom
Uniform throughout

5. Atoms and Elements
Atomic Mass
Atomic Number

6. Let’s break it down…. Elements are arranged by atomic number
Atomic number = # of protons
Protons (+) = Electrons (-) because Atoms are electrically neutral
Not all elements are atoms
Elements can be atoms, ions or isotopes
Atomic mass = protons (+) + neutrons (0) (all the particles in the nucleus)
Electron configuration (placement of electrons in different energy levels) determines how atoms react
The most important electrons are the valence electrons (the one’s found on the outermost energy level)

7. Elements bond to create Compounds. Why?
Elements are trying to be stable
Become like a noble gas (electronically speaking)  get a full outer energy level
It is all about VALENCE ELECTRONS

8. Different Types of Bonding
Ionic vs. Covalent
Polar covalent vs. Nonpolar covalent
Hydrogen

9. Ionic vs. Covalent Ionic Covalent Called a Formula unit
Called a Molecule
Type of Elements
Metal and Nonmetal
Nonmetals only
Method of Bonding
Exchange electrons:
Metals lose electrons (+)
Nonmetals gain electrons (-)
Share electrons:
Polar –unequally
Nonpolar –equally

10. Covalent bonding
Ionic bonding

11. Polar covalent vs. Nonpolar covalent
Polar: shares electrons unequally
Results in charged ends
Nonpolar: shares electrons equally
Results in molecule not having a charge

13. Hydrogen Bonding Weak bond between two separate molecules
Does not create a compound

14. Organic vs. Inorganic Compounds
A way to classify compounds
Organic – contains carbon and hydrogen often along with other elements
Examples:
Hydrocarbons such as oil, coal and gasoline
Plastics
Proteins, Carbohydrates, Lipids, Nucleic Acids
Inorganic – does not contain carbon along with hydrogen
Examples: CO2, Salt (NaCl), Water (H2O)

15. Solutions Type of Homogeneous Mixture
Can be a liquid (like kool-aid), a gas (like air), or a solid (like stainless steel)
Rule of thumb….”Like dissolves like”
“Like”= polarity = charges
Polar solvents like water will dissolve polar or ionic solutes like sugar and salt
Polar solvents like water will not dissolve nonpolar solutes like oil

16. Water is making hydrogen bonds with sodium and chloride ions (salt)
pulling them away from one another thus dissolving them….
forming a solution

17. Water
Abundance is reason why there is life on Earth

18. Properties of Water Cohesion creates Surface tension Adhesion
Water can bond to itself
Droplet shape
Adhesion
Water can bond to other molecules
Water soaks into a papertowel
Capillary action
Water can move up hollow tubes
Reason why a tree can take water from the soil to its leaves where photosynthesis occurs
High specific heat (resists changes to temperature)
Reason why water is used to cool a hot metal pan
The “lake effect”
Ice is less dense then liquid water
Honeycomb crystalline solid shape takes up more space then liquid water
Ice fishing
Universal solvent
Polar nature allows it to make hydrogen bonds and dissolve ionic and polar solutes

19. Acids and Bases
In order to be considered an acid or base it must be an aqueous solution (water-based)
In any water solution…
Water (H2O) separates into hydrogen (H+) ions or hydroxide (OH-)ions
More (H+) = Acid
More (OH-)= Base

20. pH scale Same amount of H and OH Water is H2O or HOH Start with H-
(Another word for Base)
Start with H-
Like HCl
Lots of hydrogen ions
End with –H or –OH
Like NH3 or NaOH
Lots of hydroxide ions

21. Macromolecules Four Classes Polymers made up of Monomers Carbohydrates
Lipids
Proteins
Nucleic Acids
Polymers made up of Monomers

22. Carbohydrates “1 Carbon: 2 Hydrogen: 1 Oxygen” ratio
Monomers are called monosaccharides
Glucose is a monosaccharide
Polysaccharides like starch are made of many monosaccharides
Mostly used for energy
Some used for support…
Cellulose (we call fiber) makes up cell walls of plants
Chitin is another polysaccharide
Forms the outer coverings of insects and crustaceans

23. Lipids Higher ratio of Carbon: Hydrogen bonds
Nonpolar– does not dissolve in water
Different classes
Triglycerides: fats and oils –store energy
Phospholipids: Make up cell membrane
Waxes: makes up biological structures like beehives
Steroids: hormones (estrogen and testosterone) as well as cholesterol

24. Proteins Proteins make up muscle and tissues
Enzymes are another type of important protein
Catalysts that speed up reactions
Lactase is an enzyme necessary to break down lactose
Monomers are called AMINO ACIDS
20 different amino acids
DNA contains the code that defines which amino acids link together to create various proteins that will in turn create you

25. Nucleic Acids Monomers are called nucleotides Two types: DNA and RNA
Direct protein production