Review

• Organic chemistry is the study of carbon containing molecules.
• There are multiple ways to write the structure of an organic molecule:
  • Line structures
  • Condensed formulas
  • Showing the hydrogen atoms or having them assumed
• Saturated molecules contain only single carbon-carbon bonds and unsaturated molecules contain at least one multiple bond.
• The alkane naming system for saturated hydrocarbons without branches uses the number of carbon atoms, the associated prefix, and the “-ane” ending.
• When naming branched singly bonded organic molecules (alkanes):
  • Use the “organic” nomenclature (meth-, eth-, prop-, etc.) with an “-ane” ending for the main (longest) chain.
  • List the branches in alphabetical order indicating the number of the same kind of branches using the Greek prefixes of di-, tri-, tetra-, etc. The locations of the branches need to be indicated by using the lowest sum of the branch positions along the main carbon chain.
• When naming organic molecules containing multiple bonds:
  • Add the ending “-ene” for double bonds and “-yne” for triple bonds.
  • If there are multiple double or triple bonds insert the Greek prefix for the number of multiple bonds between the stem and the ending “ene” or “yne.”
  • State the location of the starting carbon where the multiple bond(s) is/are located before the chain name.
  • If there are branches, describe how many carbons are in the branch and add the “yl” ending.
  • If there are multiple branches with the same number of carbon(s), state how many of the branches of that kind there are using the Greek prefixes “di”, “tri,” “tetra,” etc.
  • State the location of the branches giving them the lowest numbers, but the multiple bonds will determine the direction in which the main chain is numbered.
• When naming organic molecules arranged in a ring or cyclic structure insert “cyclo” between the location of the multiple bond and the stem indicating the number of carbons in the main chain.
• Alcohols contain a hydroxyl group (-OH) attached to a carbon chain. To name an alcohol the final “-e” of the carbon chain name is dropped and replaced with “-ol.” If the OH groups can be placed on different numbered carbons, the location of the OH group must be included.
• Ethers contain an oxygen atom between two carbon atoms.
• Aldehydes contain an oxygen atom doubly bonded to a carbon atom and that same carbon atom needs to have a hydrogen atom attached to it. In practice, that means the double bonded oxygen atom is on the end of the chain.
• Ketones contain an oxygen atom doubly bonded to a carbon, and that same carbon needs to have carbon atoms attached to both sides of it. In practice, that means the double bonded oxygen atom is not on the end of the chain.
• Carboxylic acids contain an oxygen atom doubly bonded to a carbon and that same carbon needs to have hydroxyl group (-OH) attached to it. In practice, that means the acid functional group is on the end of the chain and therefore does not need a number.
• Esters contain an oxygen atom doubly bonded to a carbon and that same carbon needs to have a singly bonded oxygen attached to it. That singly bonded oxygen needs to have a carbon attached to its other side. In other words, the H of the OH group in a carboxylic acid functional group has been replaced by one (or more) carbon atoms.
• When naming hydrocarbons that contain one or more halogen atoms:
  • Name the carbon chain and treat the halogens as branches, using bromo- for bromine, “chloro-“ for chlorine, “fluoro-“ for fluorine, and “iodo-“ for iodine.
  • The halogens are listed in alphabetical order preceding the carbon chain name.
• Addition reactions occur when a reactant is added to a carbon-carbon multiple bond in an unsaturated hydrocarbon.
• Substitution reactions occur when one or more hydrogen(s) are replaced by a reactant.
• Dehydrogenation reactions occur when hydrogen atoms are removed from a hydrocarbon and an unsaturated hydrocarbon is produced.
• Elimination reactions occur when a simple molecule is removed from adjacent carbon atoms forming the simple atom and an unsaturated hydrocarbon.
• Aromatics are a special group of unsaturated cyclic hydrocarbons with delocalized electrons. The simplest is benzene or 1, 3, 5-cyclohexatriene.
• When naming aromatics, if there are branches attached to a benzene ring structure, add the name(s) of the branches, then tell the location(s) of the branches.
• Polymers are very large (macromolecules) that are made up of monomers, which are small repeating units.
• Proteins, carbohydrates, and DNA are types of polymers.
• Polymers are formed through addition reactions.
• Polymers can also be formed through condensation reactions.

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