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CHEMISTRY
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Unit 1: The Basics	Unit 2: Blessed Be The Bonds That Tie	Unit 3: The Taming Of The Mole	Unit 4: Chemistry In Everyday Life	Unit 5: The Part Of Tens	Lesson 1 Why we need Chemistry	Lesson 2 Matter & Energy	Lesson 3	Lesson 4 The Periodic Table	Lesson 6
Lesson 7 Sharing the Joy: Covalent Bonding	Lesson 8	Lesson 9	Lesson 10	Lesson 11	Lesson 12	Lesson 13	Lesson 14	Lesson 15	Lesson 16
Lesson 17	Lesson 18	Lesson 19	Lesson 20	Lesson 21	Lesson 22	Lesson 23	Lesson 24	Lesson 25	Lesson 26

NOTES ON CHEMISTRY

Cook/Clean/Use Fingernail polish remover.
Synthesis: make new compounds.
Chemistry needed to understand Biology, Geology, Physics ... even Agriculture
Arithmetic, Some Algebra, A Scientific Calculator capable of exponents & logarithms
How we'll progress:

UNIT 1: THE BASICS

Definition
Why should Chemistry be important to us?
The 3 states of Matter: How to get from one to the other; the Energy changes that occur.
The Macroscopic World: Icebergs & Melting Ice.
The Microscopic World.: Atoms, Protons, Electrons. Neutrons.
How to use the Periodic Table
The Atomic Nucleus: Radioactivity, Carbon-14 dating, Fission & Fusion Nuclear Reactors,
COLD FUSION.

UNIT 2: BLESSED BE THE BONDS THAT TIE

Bonding: the good stuff
Ionic bonding: how table salt is made
Covalent bonding: Water
How to name Ionic Compounds
How to draw Lewis Structural formulas of covalent bonds
What molecules look like
Chemical Reactions: different kinds & how to balance them
Factors affecting Speed of Reactions
Electron transfer in Redox reactions involved in Electroplating & Flashlight Batteries
LETS' SEE THE LIGHT!

UNIT 3: The TAMING OF THE MOLE (Or The Shrew, As You Like It!)

Mole the central concept of chemical calculations
Amount of reactants needed in chem reactions, the amount of product formed
Solutions & their concentrations
Why I leave antifreeze in my radiator in summer, why I add rock salt to ice when making ice cream
Sour & Bitter details about acids, bases, pH, Antacids
We become Lawyers: Boyle's, Charles's, Gay-Lussac's, Combined Gas, Ideal Gas, Avogadro's etc...

UNIT 4: CHEMISTRY IN EVERYDAY LIFE:
BENEFITS & PROBLEMS

Chemistry of Carbon: Organic Chemistry
Hydrocarbons: Sources Of Energy. Organic Functional Groups
The refining of Petroleum into Gasoline. Synthesis Of Polymers
Different types Of Polymers.
Chemistry At Home: Cleaners, Detergents, Antiperspirants, Cosmetice, Hair-Care products. Medicines.
Air & Water Pollution.
DON'T GET LOST IN THE SMOG....!!

UNIT 5: MISCELLANY

Accidental Chemical Discoveries
Great Chemists
Useful Chemistry Internet Sites
Oh, for a glass of ethanol, a song, & thee .... http://skynet.oir.ucf.edu/~mschell/Chemistry/
How to deal with Math problems, Scientific Units, How to handle really big or small numbers, Conversion Method, How to report answers using significant figures.

I: What is Chemistry, Why do I need to Know some?

Objectives:
1. Defining Chemistry
2. Checking out General Areas of Chemistry
3. Discovering how Chemistry is all around us

Science: A method for examining the physical universe; a way of asking & answering questions.
Scientists: People who've never lost their wonder of nature & the desire to know.
Matter: Anything that has mass & occupies space. Pure substances or a mixture.
Chemical Change OR Chemical Reaction: Change of one substance into another

Fields Of Chemistry:
1. Analytical Chemistry: What substances are in a mixture (qualitative analysis) or how much of a particular substance is present (quantitative analysis).

2. Biochemistry: Living organisms & sytems. Chemical reactions occuring at molecular levels. A Molecular Biologist is less concerned with the chemical reactions, and more concerned with the effects on living systems.
3. Biotechnology: Application of biochemistry & biology when creating or modifying genetic material or organisms for specific purposes.
4. Inorganic Chemistry: Study of inorganic substances e.g. salts. Study of everything except Carbon.
5. Organic Chemistry: Study of Carbon & its compounds. Polymers. Petrochemicals. Pharmaceuticals.
6. Physical Chemistry: Study of the physical properties & behaviour of matter.

The Scientific Method:
1. Observe
2. Raise Questions
3. Form a Hypothesis (an educated guess).
4. Design experiment to Test hypothesis.
4. Collect data.
5. Reproduce the result.
6. Form a theory (a hypothesis that has been proved).

A Theory or Model attempts to explain why something occurs.

Macroscopic World can be seen, touched, felt. The world of experiments.
Microscopic World: Can't directly see or touch or feel. Mentally translate results of experiments.

Pure Chemistry: Usually in educational institutions. Free to carry out whatever research interests you, without expectation of practical application. Generates data & information.
Applied Chemistry: Usually in private corporations: specific goal & target. Uses data & information.

Science: Knowledge for knowledge's sake.
Technology: Application of science towards a specific goal

What does a Chemist do all day? What do they do for a living?
1. Analyze substances
2. Create, or synthesize, new substances
3. Create models & test the predictive power of theories. Theoretical Chemistry. Maths & Computers.
4. Measure the physical properties of substances.

Where do chemists work?
1. Quality Control Chemists: analyze materials to make sure they fall within specifications.
2. Industrial Research Chemist: develop new products or improve existing ones.
3. Sales Representatives: Contact customers.
4. Forensic Chemist: Analyze samples from crime scenes.
5. Environmental Chemist: Nature & Chemistry. EPA, Dept. of Energy.
6. Preservation of Art & Historical Works: Statues, historical works, etc.
7. Chemical Educator: Teach Physics & Chemistry in Schools
8. Law, Medicine, Tech writing, Consulting, etc.

Chemistry is an integral part of our world, and knowing something about chemistry helps us interact more effectively with our world.

II: MATTER & ENERGY

Objectives:
1. Understanding the states of Matter & their changes.

2. Differentiating between Pure Substances & Mixtures..
3. Finding out about the Metric System.
4. Examining the properties of chemical substances.
5. Discovering the different types of energy.
6. Measuring the energy in chemical bonds.

Matter: Has mass, occupies space

States Of Matter:
1. SOLIDS: definite shape, definite volume, Crystal Lattice.
2. LIQUIDS: no definite shape, but have definite volume.
3. GASES: no definite shape or volume, expands to fill area that contains it.

Change of state: Matter goes from one state to another
Melting: From solid to liquid. Melting point of water: 32 degrees F, 0 degrees Celsius.
Phase change: Change of state.
Boiling point: Temp at which liquid begins to boil. Steam & Water at 100 degrees C; which is hotter?
Condensation: From gas to a liquid.
Freezing: Liquid to Solid.
Sublimation: Directly from Solid to gas. Dry ice. CO2. Mothballs. Solid air fresheners.
Deposition: Directly from Gas to Solid.

IMAGE: Classification of Matter

Matter: PURE substance OR a Mixture
Pure substance: Definite & Constant composition or make-up: Salt, Sugar
Element: A single kind of atom.
Atom: Smallest particle of an element that still has all the proerties of the element
Atoms in an element all have the same number of protons.
Element is the building block of matter.
Compound is composed of 2 or more elements in a specific ratio.
Water. H2O
Components of a compound can't be separated easily; chemical reaction needed.
Mixtures: Physical combinations of pure substances that have no definite or constant composition.
Mixing a Margarita! Tequila + Triple sec in varying combinations.

IMAGE: Mixing a Margarita

Each ingredient retains its own set of physical & chemical properties.
Mixtures can be separated.easily (Sand & Salt); compounds cannot.

Homogeneous mixtures: solutions. Uniform in composition. Sugar + Water
Heterogeneous mixtures: a mixture whose composition varies from position to position within the sample. Sugar + Sand.

MEASURING MATTER

Scientists speak the same language to communicate things like mass, weight, volume, temperature.
System International: SI system. Like the Metric system.
Kilo: 1000
centi-: 0.01
milli-: 0.001
mg = 0.001 gm
1000 mg in 1 gm
Meter. 1.094 yards in 1 meter. 2.54 cm = 1 inch. 454 gm = 1 pound 0.946 liter = 1 quart
Express the weight of a 5-pound sack of potatoes in Kg. (2.3Kg)

PROPERTIES OF MATTER
Chemical & Physical
Chemical properties: enable a substance to change into a brand-new substance, & how a substance reacts with other substances. Na + Water? Does it burn in air?
Physical properties: describe the physical characteristics of a substance. Mass, Volume, colour, electrical conductivity. Extensive & Intensive properties.
Extensive: that depend on amount of matter present. Mass, Volume
Intensive: Colour. Small chunk, large chunk of Gold have the same colour.

DENSITY:

d=m / v
Quartz, Diamond have different densities. g/ml , g/cm3, g/cc
density at 20C. Water at 20C is 1g/ml.
1 cc = 1 ml. 10cc injection = 10 ml

SPECIFIC GRAVITY:

Ratio of the density of a substance to the density of water at the same temperature.

MEASURING DENSITY:
Volume of a solid is equal to the volume of water it displaces

IV: SAGA OF A TABLE

Objectives:
1. Understanding PERIODICITY

2. Figuring out how elements are organized in the periodic table.

Classification: Putting things in groups based on similar properties
Makes it easier to study a particular system

Periodicity: The pattern of repeating order
1800s: Mendeleev arranged in increasing atomic mass; was able to predict the properties of then-unknown elements.
Later, by increasing atomic number.
109+ elements
Simply learn the properties of families of elements, saving a lot of time & effort.
Figure out relationships among elements & formulas of many different compounds by referring to the periodic table.

Atomic No.
Element symbol
Atomic Mass

Horizontal Rows: 7 Periods
Vertical columns: Groups OR Families

Classification in 2 ways:
Metals. Non-Metals. Metalloids.
Families and Periods

Metals, Non-Metals, Metalloids:
Metals: Left of stairs between B and Po, except Ge & Sb.
Solid, Shiny, Good conductors of elctricity & heat, ductile, malleable. Lose electrons easily.

Non-Metals: Right of stairs between B & Po.
Brittle, Not malleable or ductile, poor conductors. Gain electrons in chemical reactions. Some are liquids.

Metalloids: Semimetals
Border the stairs. Cross between metals/non-metals. Partially conduct electricity. Valuable in computer chips, semiconductors. Si.

Families & Periods:
HPeriods: 7 Horizontal rows. Atomic Numbers increase left to right. Don't have similar properties.
VFamilies: Similar Properties. 1A: Li to Fr have similar properties: lose one electron. VIIA: Gain 1 electron.

Lets examine 4 specific families:
1A: Alkali metals. Lose 1 electron. Na, K. Important role in our body.
2A: Alkaline Earth metals. Lose 2 electrons. Ca. for healthy teeth & bones.
7A: Halogens. Gain 1 electron. Cl, Br, I. Table salt, bleach, Tincture Iodine.
8A: Noble gases. Inert, Very unreactive. Reacts only under special conditions.

Some similarities in each group in terms of their valence electrons.
Valence electrons are the s & p electrons in the outermost energy level of an atom.

VII: SHARING THE JOY: COVALENT BONDS

Objectives:
1. To see how one H atom bonds to another H atom

2. Defining covalent bond
3. Different types of Chemical Formulae
4. Polar covalent bonding & electronegativity
5. The unusual properties of water.

Ionic Bond: Chemical bond that results from the transfer of electrons from a metal to a nonmetal, resulting in the formation of oppositely charged ions - cations (positive charge) and anions (negative charge). Driving force is achieving a filled valence energy level, completing the atom's octet.

Covalent bond: Results from sharing electrons, not gaining or losing electrons. A chemical bond that comes from the sharing of one or more elctron pairs between two atoms.

H: Hydrogen
Found in nature as H2. Diatomic molecule. One valence electron. Needs 1 more electron to fill its 1s energy level, to make isoelectronic with He. H shares electrons

http://library.thinkquest.org/27819/media/covalent.gif

Electron dot formula. Lewis structural formula

6 other elements in diatomic form: O2, N2, F2, Cl2, Br2, I2

Ionic bonding: Metal.Non-metal; Solids at room temp.; much higher melting point, tend to be electrolytes.

Covalent bonding: Non-metals; Solids, Liquids or Gases at room temp; Lower melting point; Nonelectrolytes.

Metals: Alloys, Metallic bonding: sea of electrons. Move freely, hence conductors of heat & electricity.

Multiple bonds: N needs 3 electrons. VA. Triple bond. TNT. Ammonium nitrate. CO2: C has 4 valnce electrons, O has 6. C shares 2 of its valence electrons with each of the two O atoms, forming 2 double bonds.

Molecule: covalently bonded.
Formula unit: Ionic bonded.

Binary Covalent Compounds:
CO2, P4O10, SO3, N2O4. usually binary nonmetal compounds. However, MnO2 called Manganese dioxide.

Empirical Formula indicates the different types of elements in a molecule & the lowest whole-number ratio of each kind of atom in the molecule. C2H6O OR C4H12O2 OR C6H18O3.

Molecular formula OR True formula (Actual formula): C2H6O OR C4H12O2 OR C6H18O3.
C2H6O: Dimethyl Ether & Ethyl Alcohol

Octet Rule: Each atom in the compound ends up with a full octet of 8 electrons filling its valence energy levels.

Isomers: Same molecular formula, different structures.

Structural formula: shows the elements in a compound, the exact number of each atom in the compound, and the bonding pattern for the compound.

Writing the electron-dot formula for water:
1. Write a skeletal structure showing a reasonable bonding pattern using just the element symbols.
2. Take all valence electrons from all the atoms and put them in the electron pot.
3. Use N-A=S formula: Needed - Available = Shared to find number of bonds in the molecule
Water:
N= 8 + 2(2) = 12 (8 valence electrons for the O atom, plus 2 each for the 2 H atoms)
A= 6 + 2(1) = 8 (6 valence electrons for the O atom, plus 1 for each of the 2 H atoms)
S= 12-8= 4 (4 electrons shared in water), and S/2= 2bonds

Therefore 2 bonds (two shared pair of electrons) in water.
4. Distribute the electrons from the electron pot to account for the bonds.
5. Distribute the rest of the electrons (normally in pairs) so that each atom achieves its full octet of electrons.

Writing the Lewis formula for C2H4O:

N = 2(8) + 4(2) + 8 = 32 (2 carbon atoms with 8 valence electrons + 4 hydrogen atoms with 2 valence electrons each, plus an O atom with 8 electrons)

A = 2(4) + 4(1) + 6 = 18 (4 electrons for each of the two carbon atoms, plus 1 electron for each of the 4 hydrogen atoms, plus 6 valence electrons for the oxygen atom)

S = 32-18 = 14, and S/2 = 14/2 = 7 bonds.

Attractive forces : Electronegativity

When two atoms involved in a bond aren't the same, the two positively cahrged nuclei have different attractive forces and 'pull' on the electron pair to different degrees. The elctron pair shifts to one atom.

Electronegativity is the strength an atom has to attract a bonding pair of electrons to itself.

Nonpolar covalent bond: A bond in which the elctron pair is equally shared. Cl2
Polar covalent bond: A bond in which the electron pair is shifted toward one atom. HCl.
Ionic bond: NaCl: very polar.

Electronegativity difference & type of bond formed:
0.0-0.2: nonpolar covalent
0.3 - 1.4: polar covalent
>1.5 ionic.

Dipole: Molecule with a +ve and a -ve end.
Partial charge: -d (Greek)
Because polar covalent bonded molecule has a +ve end and a -ve end, it can attract the part of another molecule with the opposite charge.

WATER:

Polar covalent bonds. Solid, Liquid & Gas states can be present in close proximity. Floats in solid state. Dissolves many chemical substances, also polar covalent substances such as alcohol & organic substances. Universal solvent. Absorbs heat. Dipole. Acts like a magnet. Intermolecular force of 3 types.

1. London force / Dispersion force: Nonpolar covalent molecules. N2. H2. CH4. Weak & very brief charge separation around the bond. Very weak.
2. Dipole-dipole interaction: +ve end of one dipole attracted to -ve end of another. Weak.
3. Hydrogen bond: H to O, N or F. dipole-dipole interaction. extremely elctronegative elements. Highly polar. Water's high boiling point, ability to absorb heat. Freezing locks water into an open lattice. Large holes.

WHAT WATER REALLY LOOKS LIKE: THE VSEPR Theory:

Molecular geometry: how atoms are arranged in 3-d space. Side reactions. Why water is a dipole & CO2 is not.
VSEPR (Valence Shell Electron-Pair Repulsion) Theory allows the prediction of molecular geometry of molecules. Electron pairs around an atom try to get as far apart from each other in space.
Electron-pair geometry: arrangement of electron pairs around a central atom.

TO DETERMINE MOLECULAR STRUCTURE USING VSEPR:

1. Determine "Lewis Formula" of the molecule
2. Detremine total no. of electron pairs around the central atom.
3. Determine electron-pair geometry
4.

VIII: CHEMICAL REACTIONS

Objectives:
1. Differentiating between reactants & products
2. Finding out how reactions occur
3. Taking a look at Different types of Chemical Reactions
4. Polar covalent bonding & electronegativity
5. The unusual properties of water.

Nonpolar covalent bond: A bond in which the elctron pair is equally shared. Cl2
Polar covalent bond: A bond in which the electron pair is shifted toward one atom. HCl.
Ionic bond: NaCl: very polar.

Electronegativity difference & type of bond formed:
0.0-0.2: nonpolar covalent
0.3 - 1.4: polar covalent
>1.5 ionic.

Dipole: Molecule with a +ve and a -ve end.
Partial charge: -d (Greek)
Because polar covalent bonded molecule has a +ve end and a -ve end, it can attract the part of another molecule with the opposite charge.

WATER:

Polar covalent bonds. Solid, Liquid & Gas states can be present in close proximity. Floats in solid state. Dissolves many chemical substances, also polar covalent substances such as alcohol & organic substances. Universal solvent. Absorbs heat. Dipole. Acts like a magnet. Intermolecular force of 3 types.

1. London force / Dispersion force: Nonpolar covalent molecules. N2. H2. CH4. Weak & very brief charge separation around the bond. Very weak.
2. Dipole-dipole interaction: +ve end of one dipole attracted to -ve end of another. Weak.
3. Hydrogen bond: H to O, N or F. dipole-dipole interaction. extremely elctronegative elements. Highly polar. Water's high boiling point, ability to absorb heat. Freezing locks water into an open lattice. Large holes.

IX: ELECTROCHEMISTRY

Objectives:
1. Find out about redox reactions
2. Find out how to balanc redox reactions
3. Taking a look at Different types of Chemical Reactions
4. Polar covalent bonding & electronegativity
5. The unusual properties of water.

Nonpolar covalent bond: A bond in which the elctron pair is equally shared. Cl2
Polar covalent bond: A bond in which the electron pair is shifted toward one atom. HCl.
Ionic bond: NaCl: very polar.

Electronegativity difference & type of bond formed:
0.0-0.2: nonpolar covalent
0.3 - 1.4: polar covalent
>1.5 ionic.

Dipole: Molecule with a +ve and a -ve end.
Partial charge: -d (Greek)
Because polar covalent bonded molecule has a +ve end and a -ve end, it can attract the part of another molecule with the opposite charge.

WATER:

Polar covalent bonds. Solid, Liquid & Gas states can be present in close proximity. Floats in solid state. Dissolves many chemical substances, also polar covalent substances such as alcohol & organic substances. Universal solvent. Absorbs heat. Dipole. Acts like a magnet. Intermolecular force of 3 types.

1. London force / Dispersion force: Nonpolar covalent molecules. N2. H2. CH4. Weak & very brief charge separation around the bond. Very weak.
2. Dipole-dipole interaction: +ve end of one dipole attracted to -ve end of another. Weak.
3. Hydrogen bond: H to O, N or F. dipole-dipole interaction. extremely elctronegative elements. Highly polar. Water's high boiling point, ability to absorb heat. Freezing locks water into an open lattice. Large holes.