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Glossary Of Organic Chemistry

Contents
  Organic Formulas Ethers
  Alkanes Carbonyl Compounds
  Alkenes Alcohols
  Alkynes Organic Acids
  Dienes, Trienes Esters
  Aromatic Hydrocarbons Amines
  Alkyl Petroleum Processing
 

The Meaning Of Organic

Originally it meant from Living Substances. The Vital Force (force of life) was needed to create organic substances. But in 1828 Woller synthesized Urea from non-vital materials. Now Organic Chemistry is the study of Carbon Compounds.

Comparison of the Organic vs Inorganic Compounds:

INORGANIC about 100,000; ORGANIC over 8 million and increasing by 300,000 per year.

Reasons why there are so many organic compounds:

  1. Carbon forms stable bonds with itself to make chains.
  2. Carbon forms stable bonds with most other elements.
  3. Carbon forms branched chains.
  4. Carbon forms ring chains.
  5. Carbon forms double bonds.
  6. Carbon forms triple bonds.
  7. Carbon forms cis-trans isomers.
  8. Other elements may interrupt the chain.
  9. All of the above may occur together.

Inorganic/Organic

High melting point / Low melting point
High boiling point / Low boiling point
Non-volatile / Volatile liquids
Have fast reactions / Have slow reactions

Organic Formulas:

Molecular formulas show ratio of atoms, ie. C5H12

Structural formulas show arrangement of atoms.

Condensed Structural formulas reduces to one line.

Isomers same molecular formula with a different structure. ie. C40H82 has 60 trillion isomers!

Alkanes:

The Homologous Series: The first decalog

Methane CH4 - Ethane C2H6 - Propane C3H8 - Butane C4H10 - Pentane C5H12 - Hexane C6H14 - Heptane C7H16 - Octane C8H18 - Nonane C9H20 - Decane C10H22

Naming Alkanes
End in -ane

Alkane Reactions - Mostly Inert
No reaction with b acids, bases, and redox agents. ex. plastics.

Halogen Substitution
With ultraviolet light to break b covalent bonds. Then halogens can replace the hydrogens.

Nitration
Nitric acid HO-NO2 replaces hydrogens with nitro groups -NO2. These are the nitro compounds.

Combustion ("burn it")
Add oxygen and get CO2 and H2O

Pyrolysis (Cracking)
Heating sans oxygen yields various sub products.

The Wurtz Reaction to Lengthen the Chain

A) Halogen Substitution to put chlorine on the chain, R = any alkyl group (alkane, alkene, alkyne).

B) The WURTZ: Sodium rips off the chlorines so that two R groups will join together to form a compound of double the number of carbons.

Alkenes:

Naming Alkanes
End in -ene.

Carbon - Carbon Double Bonds
They have C=C bonding.

Properties of the Double Bond
Highly reactive because andemdash; the carbons are closer together. The double bond prevents rotation and allows the formation of CIS-TRANS ISOMERS andemdash; Extra pair of electrons are not so bly held (greater dist, from nucleus). Energy of extra pair not needed for bonding so their energy is available for reacting. The extra pair (buns) is out where the action is.

Alkene Reactions - Halogen Addition
Halogens will break the second bond and add thereto and making an alkane.

Test for the Double Bond
Add bromine and the red colour disappears as the bromine is added to the double bond as in the above reaction.

Polymerization
Building up large molecules from small repeating units using a catalyst to cause polmerization. Examples are plastics, synthetic fibers, and rubber.

n = a very large number (thousands of units).

cat n H2C=CH --> -(-CH2-CH-)-n PVC (poly vinyl chloride) | poly | (plastic pipe) Cl Cl

cat n CH2=CH --> -(CH2-CH-)-n (polystyrene) | poly | (styrofoam) C6H6 C6H6

cat n CH2=CH --> -(CH2-CH-)-n (nylon, orlon) | poly | CN CN

Polytetrafluoroethene "TEFLON" a completely halogenated and saturated hydrocarbon

F F F F F F F cat | | | | | | | n CF2=CF2 --> F-C-C-C-C-C-C-C-C- poly | | | | | | | F F F F F F F

Alkynes:

Carbon-Carbon Triple Bond

Reactions are like those of the alkenes except they may happen twice, once for each of the extra bonds.

Preparation Of Alkynes
Coke + lime -->
calcium carbide + carbon monoxide 3000C 3 C + CaO --> CaC2 + CO

CaC2 + 2H2O --> H-C = C-H + Ca(OH)2 acetylene On burning it's, "Ah, the LIMELIGHT"

2C2H2 + 5O2 --> 4CO2 + 2H2O

Dienes, Trienes, Etc.

Dienes, Trienes, etc. Have more than one set of double or triple bonds.

Rubber
2-methyl-1,3-butadiene polymerizes like this:
cat n CH2 =CH-C=CH2 --> -(CH2-CH=C-CH2)-n | poly | CH3 CH3 rubber

Vulcanizing Rubber
Cross links long chains (with sulfur chains so they won't come apart when pulled

Aromatic Hydrocarbons

The Benzene Ring
A conjugated system of alternate double and single bonds. The electrons are delocalized, spread out to give a uniform electron cloud around the molecule.

Benzene
C6H6, the beginning substance of an enormous number of organic chemicals and biological substances.

Toluene
1-methylbenzine, the starting compound for many useful organic compounds. Ex 2,4,6-trinitrotoluene, "TNT".

Naphthalene
Two benzine rings attached together. The beginning substance for a multitude of important compounds such as dyes.

Older System of Naming Benzenes
Para, ortho, and meta positions on the benzine ring. ie. paradichloro benzene, moth crystals.

Phenols
have the -OH group attached to the benzene ring. Starting compounds for another huge family of organic substances.

Alkyl

Alkyl group is any Alkane, Alkene, or Alkyne. An Aromatic group is any compound having a Benzene structure.

ETHERS

Ethers have an oxygen separating two or more alkyl groups. R-O-R, R-O-Arc etc.

ie. methoxyethane, CH3-O-CH2CH3. Hospital ether is ethoxyethane (or diethyl ether).

Carbonyl Compounds

Carbonyl compounds have a double bonded oxygen attached to a carbon.

--C=O | ALDEHYDES-- have the carbonyl group at the end of the chain. R-C=O | or RCHO end in -al. H ie. methanal (formaldehyde) H-C=O | H KETONES-- have the carbonyl group not at the end of the chain.

R--O=O number where it is and it ends in -one. | CH3 R' | ie. O=C-CH2-CH2-CH3 2-pentanone

Alcohols

"evil spirits" have an -OH group on the carbon chain.

Common Alcohols
methanol, CH3OH, "wood alcohol". ethanol, CH3CH2OH, "booze". 2-propanol, CH3CH2CH3,, "rubbing alcohol". | OH

Naming Alcohols
number where it is and it ends in -ol.

CH3-CH2-CH-CH3 | 2-butanol OH

Denatured Alcohol
has government poisons added to discourage drinking it. This is done to industrial ethanol so that the liquor tax is not charged for industrial usage.

Absolute Alcohol
is 100% pure ethanol. This can only be accomplished by a chemical process to remove the last 5% of water. It is used for special chemical reactions where water must be absent. (At 95%, the water-ethanol mixture becomes azeotropic which means that the common boiling points prevent further separation by distillation).

Proof of Alcohol
a test used by early California miners to be sure the barkeep had not watered down the whiskey. Gun powder soaked in whiskey will burn if it is at least 50% ("good stuff"). This is "proof" that all is OK. Since a score of "100" was given for good work, 50% was "100 proof" that there was no foul play. Hence proof is twice the percentage. (Another typical US measurement!)

Preparation of Alcohol
Fermentation of carbohydrates
yeast C6H12O6 --> 2 CH3CH2-OH + 2CO2 enzymes

Organic Acids

The Carboxylic Acid Group
R--C=O -oic acid | O-H

Common Acids
Methanoic acid (formic acid)-- bee stings.
Ethanoic acid (acetic acid)-- vinegar.
Butanoic acid (yuk)-- essence of barf.

Salicylic Acid
Phenol with an acid group attached. Part of aspirin.

Esters

Esthers are compounds derived from the reaction of an organic acid with an alcohol. Acid + alcohol --> ester + water

R--C=O + R'--OH --> R--C=O + H2O | | C-OH C-O-R'

Esters are the compounds that give fruits their characteristic flavors and odors. ie. methyl salycilate is "Oil of Wintergreen".

Amines

Amines have the NH2 group R-NH2

Naming Amines
End is -amine
CH3-CH2-NH3 Ethyl amine
As in vitamines.

Petroleum Processing:

Separation Of Crude Oil Into Its Fractions:

Fractional Distillation
Each compound has its own boiling point and can be separated by distillation. Groups of compounds are called boiling fractions.

Boiling Fractions: Because these are ranges, there is an overlap of the number of carbons.

Bottle gases CH4 to C4H10 Methane, Ethane, Propane, Butane.
Petroleum Ethers C5H10 to C6H12 Highly volatile liquids for solvents.
Gasoline C7 to C12
Kerosene and Jet Fuel C12 to C16
Lubricating Oils C16 to C20
Greases C20 to C30
Paraffin Wax C30 to C40
Asphalt C60 and up

Cracking
Breaking up large oil sized molecules into smaller gasoline molecules in order to increase the amount of gasoline produced.
C16 --> 2C8 this is done by
A) Thermal Pyrolysis (heating sans oxygen so it won't burn)
B) Catalytic action The "Cat Cracker"

Polymerization
Building large molecules from smaller ones (changing butane into gasoline to increase the yield of the latter).
cat 2C4 --> C8

Reforming
Rearranging molecules to increase "octane rating." Branched and ring chains burn more slowly to increase engine performance.

Catalytic and Isomerization
Branching the chain:
C C | | C-C-C-C-C-C-C-C --> C-C-C-C-C | C Octane --> 2,2,4-trimethyl pentane (100 octane gasoline)

Octane Rating
The comparison of fuel performance in a standard test engine. The octane rating scale calls Heptane "0 octane" and 2, 2, 4 - trimethyl pentane "100 octane".

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