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Chemistry

Activities that produce one additional death per one million people exposed to the risk: smoking 1.4 cigarettes (cancer, lung disease), living 2 months with a cigarette smoker (cancer, lung disease), eating 40 tablespoons of peanut butter (liver cancer caused by the natural carcinogen aflatoxin B), drinking 40 cans of saccharin-sweetened soda (cancer), eating 100 charcoal-broiled steaks (cancer), traveling 6 minutes by canoe (accident), travelling 10 minutes by bicycle (accident), travelling 300 miles by car (accident), travelling 1000 miles by jet aircraft (accident), drinking Miami drinking water for 1 year (cancer from chloroform), living 2 months in Denver (cancer caused by cosmic radiation), 1 chest xray in a good hospital (cancer), living 5 years at the boundary of a typical nuclear power plant (cancer).
From L. Gough and M. Gough: "Risky business," Chem Matters, pp 10-12, December, 1993.

Modern Atomic Theory: the law of conservation of matter (there is no detectable change in mass in an ordinary chemical reaction), law of constant composition (a chemical compound always contains the same elements in the same proportions by mass). Assumptions: elements are composed of atoms, which are extremely tiny, all atoms of a given element have the same chemical properties and contain the same number of protons, compounds are formed by the chemical combination of two or more different kinds of atoms, atoms are the units of chemical change (chemical reactions result only in the combination, separation, or rearrangement of atoms).

ElementSymbolDate of DiscoveryDiscovererDerivation of Name or Symbol
AluminumAl1827F. WohlerL, alumen (alum)
BerkeliumBk1950G. T. Seaborg, S. G. Thompson, and A. GhiorsoBerkeley, CA, was site of Seaborg's labratory
CarbonCAncientL, carbo (charcoal)
CalciumCa1808H. DavyL, calx (lime)
CopperCuAncientL, cuprum (from island of Cyprus)
HydrogenH1766H. CavendishGk, hydro (water) and genes (former)
HeliumHe1868P. Janssen, et al. W. Ramsay (1895) from uranium mineral cleviteGk, helios (sun)
IodineI1811B. CourtoisGk, violet
IronFeAncientL, ferrum
GoldAuAncientL, aurum (bright)
MercuryHgAncientL, hydrargyrum
MendeleeviumMd1955A. Ghiorso, B. Harvey, G. Choppin, S. Thompson and G. SeaborgHonoring Dmitri Mendeleev, periodic table developer
SodiumNa1807H. DavyL, sodanum
PhosphorusP1669H. BrandGk, phosphorus
PoloniumPo1898M. CuriePoland, homeland of discoverer
SulfurSAncientL, sulphurium
TinSnAncientL, stannum

If you weigh 150lb, 90lb or 60% is water, 30lb is fat, remaining 30lb is a combination of proteins, carbohydrates and calcium, phosphorus and other dietary minerals. Nonmetals are present as anions in body fluids, including chloride ion (Cl-), phosphorus in three ionic forms (PO43-, HPO42-, and H2PO4-), and carbon as bicarbonate and carbonate ions. Metals are present in the body as cations in solution (for example, Na+, K+), in solids (Ca2+ in bones and teeth), and incorporated into large biomolecules (for example, Fe2+ in hemoglobin and Co3+ in vitamin B-12).

Carbohydrates - lit means "hydrate of carbon," makes up avg half of human diet, general formula Cx(H2O)y, where x and y are whole numbers. Glucose - C6H12O6, sucrose - C12H22O11. C's/H's/O's usually arranged in alcohol (C-H), aldehyde (C single-bonded to H and double-bonded to O; simplest in this class is formaldehyde) and ketone (C=O; simplest is acetone) functional groups. Three classes of carbs. First monosaccharides (from latin saccarum, "sugar"), glucose most important, can be either chain or circular, but usually drawn in line for simplicity. Second disaccharides, two monosaccharides joined. Sucrose is glucose and fructose (in ring forms) joined together. All mono- and disaccharide names end in -ose. Mono's/di's together called "simple sugars." Glucose also called "dextrose" or blood sugar.
SubstanceSweetness (relative to sucrose at 1.00)
Lactose (milk sugar, a disaccharide)0.16
Galactose (a monosaccharide in milk sugar)0.32
Maltose (a disaccharide used in beer making)0.33
Glucose (dextrose, a common monosaccharide)0.74
Sucrose (table sugar, a disaccharide)1.00
Fructose (fruit sugar, a monosaccharide)1.74
Aspartame (artificial sweetener, Nutrasweet)180
Saccharin (artificial sweetener)300
Third class is polysaccharides, many mono's joined together, as many as several thousand. Cellulose is one, built from glucose, fiber since we can't digest it. Starch is another glucose-based polysacc.

Fats and oils. Carboxylic acid group is present in all organic acids. Tristearin is a very common animal fat. Made out of glycerol and stearic acid (fatty acid). Glycerol has three alcohol functional groups; staric acid - like all organic acids, long chain of carbons/hydrogens, end is carboxylic acid functional group, -CO2H. In tristearin formation, carboxylic acid groups react with the three -OH groups of glycerol moledule. All fats and oils have same basic structure - three hydrocarbon chains from three fatty acids linked to glycerol. Fatty acids usu have even num carbons, 4-20. One gram of fat releases more than twice amt energy avaliable from 1g carbohydrate. Avg american diet == 37% calories from fats/oils. Nutritionists say to reduce to 30% b/c of heart disease.

Common strong acids (strong electrolytes): HCl/hydrochloric, HNO3/nitric, H2SO4/sulfuric, HClO4 (perchloric), HBr/hydrobromic, HI/hydroiodic. Weak acids (weak electrolytes): H3PO4/phosphoric, CH3CO2H/acetic, H2CO3/carbonic. Strong bases (strong electrolytes): LiOH/lithium hydroxide, NaOH, KOH, Ca(OH)2, Ba(OH)2, Sr(OH)2. Weak base (weak electrolyte): NH3/ammonia.

Activity series of metals. (Displace H2 from H2O(l), steam, or acid:) Li, K, Ba, Sr, Ca, Na, (Displace H2 from steam or acid:) Mg, Al, Zn, Cr, (Displace H2 from acid:) Fe, Ni, Sn, Pb, H2, (Do not displace H2 in any of three:) Sb, Cu, Hg, Ag, Pd, Pt, Au. A metal higher in the activity series will displace an element below it in the series from its compounds.

First Law of Thermodynamics, law of conservation of energy: energy can neither be created nor destroyed - the total energy of the universe is constant.

Average Bond Energies (in kJ/mol)
Single Bonds
IBrClSPSiFONCH
H297368431339318293569463389414436
C238276330259264289439351293347
N--243?201--209--272201159
O201--205--351368184138
F--197255285490540159
Si213289360226213176
P213272331230213
S--213251213
Cl209218243
Br180192
I151
Multiple Bonds
N=N418C=C611
N[triple]N946C[triple]C837
C=N615C=O(in CO2, O=C=O)803
C[triple]N891C=O(as in H2C=O)745
O=O (in O2)498C[triple]O1075

Sign of dHsystemSign of dSsystemProduct-Favored?
- (Exothermic)+Yes
- (Exothermic)-Yes at low T; no at high T
+ (Endothermic)+No at low T; yes at high T
+ (Endothermic)-No
Gibbs free energy: dGsystem = -TdSuniverse. A decrease in Gibbs free energy of a system is charachteristic of a product-favored process.
dGosystem = dHosystem - TdSosystem
or Gproducts - Greactants

Equantum = hvradiation where h is Planck's constant... 6.626x10-34Js, and this relates the frequency of radiation to its energy. Photoelectric effect: certain metals emit electrons when hit by light of certain wavelengths.

Agreement between Bohr's Theory and the Lines of the Hydrogen Spectrum.
Changes in Energy LevelsWavelength Predicted by Bohr's Theory (nm)Wavelength Determined from Laboratory Measurement (nm)Spectral Region
2 -> 1121.6121.7Ultraviolet
3 -> 1102.6102.6Ultraviolet
4 -> 197.2897.32Ultraviolet
3 -> 2656.6656.3Visible red
4 -> 2486.5486.1Visible blue-green
5 -> 2434.3434.1Visible blue
4 -> 318761876Infrared
Photons in the ultraviolet region are produced by electrons moving from energy levels with n > 1 to n = 1. Visible region by n > 2 to n = 2. Infrared by n > 3 or 4 to n = 3 or 4.

Alkenes - hydrocarbons w/ one or more doublebonds.
Alkynes - hydrocarbons w/ one or more triplebonds.

Odd number of valence electrons - free radicals.
Dimers - type of substance made from two smaller units. Free radicals react with selves to form these.