Carbon s unique bonding pattern arises from the hybridization of the electrons.

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1 Unit 8 Neptune, the 8 th planet of our solar system Organic Chemistry Organic: compound containing carbon, excluding oxides and carbonates Carbon is an allotrope, meaning it has different bonding patterns. There are 4 types of carbons: Amorphous Carbon Coal, no set pattern to the bonding, weak Graphite Sheets of hexagonal carbon, with weaker bonds in between the layers Diamond Perfect tetrahedral pattern Fullerenes Spheres of carbons, one atom thick ; another example of this is nanotubes Carbon s unique bonding pattern arises from the hybridization of the electrons. Sp 3 hybridization: 4 equivalent covalent bonds, new orbitals are created called sp 3 orbitals This results in 4, angles Tetrahedral shape Sp 2 hybridization: This is when carbon is double bonded 1 of the p orbitals doesn t hybridize Trigonal planar shape You get 3 sigma bonds and 1 pi bond Sp hybridization: Occurs when carbon has a triple bond Linear shape Only 1 p orbital hybridizes 2 sigma bonds and 2 pi bonds Properties of hydrocarbons:

2 Insoluble in water Lower boiling and melting point Low density Not very reactive IUPAC: International Union of Pure and Applied Physics Decide the nomenclature for compounds Hydrocarbons: Alkanes Single bonded carbon chain Longest carbon chain- prefix, then add ane Alkenes Alkynes Double bonded carbon Triple bonded carbon Longest carbonchain-prefix, then add ene, indicate where double bond is located Longest carbon chain- prefix, add yne, indicate where the triple bond is located Pentane Ethene 1-Propyne Prefix for carbon chain: 1: Meth- 2: Eth- 3: Prop- 4: But- 5: Pent- 6: Hex- 7: Hept- 8: Oct- 9: Non- 10: Dec- Numbering Carbons: Triple bonds and double bonds always get the lowest number, given priority For other functional groups, try to give them the lowest possible numbers When there are no functional groups or double bonds, find the end that has the most alkyl groups

3 Steps for naming: Find longest continuous chain Number the carbons Give name and location of each group List alphabetically Hydrocarbons are often referred to as saturated or unsaturated. A hydrocarbon is saturated when there are only single bonds and it is full of hydrogens Unsaturated can be monounsaturated or polyunsaturated. Monounsaturated is when the hydrocarbon has one bond that is double or triple where more hydrogens can be added. Polyunsaturated is where there are many double or triple bonds in the hydrocarbon Aromatics: Most common example is Benzene, C 6 H 6 All bonds are equal, they are a hybrid between single and double bonds. Referred to as resonance. Kind of a 1 and a half bond, as the double bond flips back and forth so quickly. Derivatives of Benzene: Toulene: Xylene: Ortho- The planet was named after the Roman god of the sea.

4 Meta- Para- Other functional groups: Halocarbon Alcohol Aldehyde A F, Cl, Br, I in place of a H, Use prefixes fluoro, chloro, bromo, iodo as well as indication of location An OH group, add ol to the end of the compound can be primary, secondary, or tertiary A double bonded O, add al to the end of the compound Slightly polar, higher bp and mp Polar, higher bp and mp, * Not very reactive, polar, carbonyl group chloromethane methanol Ketone A double bonded O in the middle of the chain, add one and location, carbonyl group Not very reactive, less polar than aldehydes, methanol, or AKA formaldehyde propanone, AKA acetone

5 Ether Carboxylic acid Ester Amine Oxygen in the chain of carbons, IUPAC shorty oxy langane ** Carboxyl group, terminal carbon, doubl bonded O and an OH, add oic acid to compound name Double bonded O and a single bond O, created by combining an alcohol and a carboxylic acid, name alcohol, then drop ic from acid and add -ate Nitrogen group, can be primary, secondary or tertiary, add amine to name Mostly unreactive, very flammable, relatively nonpolar Polar, more polar than alcohols, high melting and boiling point Strong aromas and flavors, lower bp and mp than alcohols and acids, low polarity Acts like an alcohol, methoxymethane methanoic acid, AKA formic acid Methyl methanoate, AKA methyl formate Amide Amino group, looks like an ester, but has a N in place of the single bonded O, add amide Semi polar, higher mp and bp methanamine methanamide *Primary is when there is just one carbon attached to the OH/N group Secondary is when there are two carbons adjacent to the carbon with the OH/N group Tertiary is when there are three carbons attached to the carbon with the OH/N group **the common system of naming is alkyl alkyl ether Polarity: from most to least Water Carboxylic acids Amides* Alcohols Amines* Aldehydes Ketones

6 Esters Amides* Ethers Amines* Halocarbons Hydrocarbons(alkanes, -enes, -ynes *depending whether it is primary, secondary or tertiary. Primary and secondary are more polar Three types of reactions of hydrocarbons: Combustion Addition Substitution Neptunes blue color is due to the absorption of red light by methane Alkanes often undergo substitutions Alkenes and Alkynes undergo addition Aromatics tend to prefer substitution, but are in general, not very reactive. Alcohols are created through a hydration reaction (addition reaction) Add water Aldehydes are created through hydrogenation Add hydrogen Ketones are created through oxidation of a secondary alcohol Add oxygen Ethers are created through a condensation reaction of alcohols Take out water Carboxylic acid is created through the oxidation of aldehydes Add oxygen

7 Esters are created through esterification, the condensation of a carboxylic acid and an alcohol Take out water Amides are created through the same process of esterification, but with an amine group rather than an alcohol Polymers: macro molecules with repeating units (monomers) Two types of polymerization: Addition The creation of a polymer by breaking the pi bond(s) of a double or triple bonded hydrocarbon and connecting long chains of the molecules Polyethylene, polypropylene, polystyrene, polyvinyl alcohol, and polyvinyl chloride are all synthesized through addition Condensation You take out a water molecule, or H 2, in order to allow for new bonds. It is much like substitution, but a special kind of substitution Polyesters, Polycarbonates, and polyamides are synthesized through this method Practice: Name the molecule: The molecule has a chain of ten carbons, all single bonded. The prefix for ten is dec- and the suffix for single bonds is ane, so the molecule is decane. I created this question.

8 The longest chain of carbons is 5 carbons long. This lends the prefix pent-; there is a double bond, so the suffix is ene, and the double bond is located on the second carbon. There is also a methyl group on the second carbon. When you put it together you get 2-methyl-2-pentene. I created this question Draw the molecule: A year on Neptune lasts 165 earth years 1-ethyl-4,5-dimethyl-2-heptyne Click here for the answer First, you would draw the 7 carbon chain, with the triple bond between the second and third carbon. Then on the second carbon, you would draw an ethyl attachment and on the 4 th and 5 th carbons a methyl group. I created this question. Guess the functional group described: 1. A compound is dissolved in water. It has a very high boiling point and melting point. When added to a solution of ethanol, a sweet aroma is produced. 2. Although normally not very reactive, a compound is found to be very flammable. 3. An unknown compound is tested; it is found to be very polar, with high boiling and melting points. When potassium dichromate, an oxidizing agent, it is found to produce a ketone. Name the functional group. 4. A compound is 14.37% hydrogen and 85.63% carbon, lending a 1 mole of carbon for every 2 moles of hydrogen, suggestive of an alkene. However, on closer inspection, this couldn t be as the compound is extremely stable. What is the compound? Answers:

9 1. The compound is a carboxylic acid. They are very polar, and when combined with an alcohol, produce an ester, as can be noted by the sweet smell. 2. This is an ether. They are very flammable, although they are not very reactive. 3. The compound is an alcohol. The polarity is indicative, but the oxidation of alcohols is known to produce ketones. 4. This compound is an aromatic to be sure. Perhaps benzene, or another derivative, or another cyclic.