Organic Chemistry: Study of carbon based molecules Bonding Covalent (share valence e-) All Nonmetals Made of carbon, hydrogen and other nonmetals like sulfur, oxygen, nitrogen etc.

Carbon Based Molecules Carbon Atoms Form the “Backbone” Carbon has 4 valence and needs 4 more ALWAYS forms 4 bonds Bonds can be single, double or triple Due to variety and number of bonds carbon can form you can have an enormous number of combinations

Properties of Organic Compounds

Melting Point Temp. Relatively Low MP (compared to ionic, metallic) MP depends on strength of IMF Non-polar molecules: (Lowest MP) Have VDW attractions (weak) Larger NP molecules have higher MP than smaller Polar molecules: (Slightly Higher MP) Dipole-dipole attractions or H-bonding Molecules held together more

Solubility Polar molecules: soluble in polar solvents like water Nonpolar molecules: soluble in nonpolar solvents like hexane Look for: Symmetry = nonpolar Assymmetry = polar

Conductivity in Solution Organic Molecules usually DO NOT ionize don’t conduct in solution NONELECTROLYTES Important Exception: ORGANIC ACIDS Ex: CH3COOH

Also… Organic Molecules: Undergo combustion in the presence of oxygen Slow rates of reaction due to complexity of bonds (often catalyst needed) Breakdown/decompose at low temperature compared to other compounds

Formula Writing and Drawing Molecules

Types of Formulas Molecular Empirical Structural Condensed Structural

Organic Prefixes (Table P) Meth Eth Prop But Pent Hex Hept Oct Non Dec Indicate how many carbon atoms are in the entire molecule You will only see molecules with a max of 10 carbons

Homologous Series of Hydrocarbons (Table Q) Have unique general “formula” Each member of the series differs by one carbon and a certain # of hydrogen

General Formula: CnH2n+2 Alkanes General Formula: CnH2n+2 All single bonds between carbon atoms Name ends in “ane” SATURATED hydrocarbons (holding as many hydrogen atoms as possible) http://www.kentchemistry.com/links/organic/orgonaming1.htm

Alkenes General Formula: CnH2n One double carbon to carbon bond *Address needed for bond location Name ends in “ene” UNSATURATED hydrocarbons (not totally filled with hydrogen) http://www.kentchemistry.com/links/organic/orgonaming2.htm

General Formula: CnH2n-2 Alkynes General Formula: CnH2n-2 One triple carbon to carbon bond *Address needed for bond location Name ends in “yne” UNSATURATED hydrocarbons (not totally filled with hydrogen) http://www.kentchemistry.com/links/organic/orgonaming3.htm

dienes, diynes etc… Have multiple double or triple bonds. Give the address for each multiple bond. End of name becomes “-diene…or –triene” Use prefix “di/tri/tetra/penta” etc…if more than one of the same thing on the chain. http://www.kentchemistry.com/links/organic/orgonaming5.htm http://www.kentchemistry.com/links/organic/orgonaming6.htm

Branching Hydrocarbons Have hydrocarbon “branches” off the main carbon chain. Called “alkyl” groups

Naming Branched Hydrocarbons Find longest continuous carbon chain and name it (parent chain) Find address of each branch Count carbons in each branch Name branches using prefix ending in “yl” Ex: 2 carbon branch would be an “ethyl” branch. Note: If more than one of the same type of branch use “di”, “tri”, “tetra” etc…instead of repeating the name

Isomers Same molecular formulas, but different structural formulas. Atoms in the molecule have a different arrangement. The more atoms the larger the number of possible isomers http://www.kentchemistry.com/links/organic/isomersofalkanes.htm

Cyclical Hydrocarbons Form rings Start with “cyclo-” http://www.kentchemistry.com/links/organic/orgonaming7.htm

Benzene Series Benzene Series: 6 carbon ring with alternating double bonds. Electrons in double bonds “resonate” between bond sites giving more strength to all the bonds Branches and functional groups are often attached to the ring Ortho/Meta/Para locations http://www.kentchemistry.com/links/organic/orgonaming4.htm

Organic Functional Groups Reference Table R

Halides Contain one or more halogen atoms. Fluoro / chloro / bromo / iodo prefix Use address Use di, tri, tetra if more than one of same http://www.kentchemistry.com/links/organic/halides.htm

Alcohols Have one or more “Hydroxyl” groups (-OH) Use address Name ends in “-ol” If more than one (–OH), name ends in “diol”, or “triol” Important Example: Glycerol or 1, 2, 3 propantriol

Types of Alcohols Primary Secondary Tertiary http://www.kentchemistry.com/links/organic/alcohols.htm

Aldehydes Carbon double bonded to oxygen at end of a carbon chain (“carbonyl” group) ADDRESS NOT NEEDED (always at end!) End in “–al” http://www.kentchemistry.com/links/organic/Aldehydes.htm

Ketones Carbon double bonded to oxygen in middle of a carbon chain (“carbonyl” group) Use address End in “-one” http://www.kentchemistry.com/links/organic/Ketones.htm

Ethers Oxygen atom within carbon chain Count carbon atoms on either side of oxygen and name them like “alkyl” branches. “Butterflies” with belly buttons http://www.kentchemistry.com/links/organic/ethers.htm

Organic Acids At the end of the carbon chain is a “carboxyl” group containing two oxygen atoms. ADDRESS NOT NEEDED (always at end!) End in “-oic acid” Has an acidic hydrogen that ionizes so these are ELECTROLYTES http://www.kentchemistry.com/links/organic/OrgAcid.htm

Esters Within the chain, there is an oxygen atom that is next to a carbon double bonded to oxygen Use oxygen inside of chain as middle point. (Sorta like an “ether” belly button) Name both sides around the oxygen atom Side with carbon “Alkyl” branch, ends in “yl” Side with the double bonded oxygen ends in “oate” http://www.kentchemistry.com/links/organic/esters.htm

Amines Have an “amine” group containing nitrogen. Use address Ends in “-amine” Important Example: Amino Acid http://www.kentchemistry.com/links/organic/amines.htm

Amides Also have a nitrogen atom, but it is next to a carbon double bonded to oxygen. End in “amide”. http://www.kentchemistry.com/links/organic/amide.htm

Organic Reactions

Combustion Burning or oxidation of a hydrocarbon. Needs O2 Produces CO2 and H2O Always EXOTHERMIC If not enough O2 present, you can get “incomplete” combustion resulting in carbon monoxide (CO) and soot (C). http://www.kentchemistry.com/links/organic/combustion.htm

Fermentation Makes ALCOHOL!!! Sugar is metabolized by yeast enzymes to make ethanol and CO2 http://www.kentchemistry.com/links/organic/Fermentation.htm

Substitution Happens with ALKANES One hydrogen atom comes off and is “substituted” for another atom. Results in TWO products Ex: Halogen Substitution http://www.kentchemistry.com/links/organic/Substituition.htm

Addition ALKENES and ALKYNES. Add atoms without removing hydrogen Double or triple bond “opens up” Two atoms “add on” for each broken bond Results in ONE product. Ex: Halogen Addition Hydrogenation http://www.kentchemistry.com/links/organic/Addition.htm

Polymerization Joining together of many individual “monomers” to make a “polymer”. Ex: Synthetic Polymers Nylon Rayon Polyethelene Polystyrene (styrofoam) Polyester Ex: Natural Polymers DNA/RNA Starch, Cellulose Proteins http://www.kentchemistry.com/links/organic/polymers.htm http://www.kentchemistry.com/links/organic/polymersswf.htm

Types of Polymerization Condensation Polymerization Remove water to join monomers Ex: Amino Acids joining to make “peptide” bonds Addition Polymerization Open up double/triple bonds to join monomers Happens to alkenes/alkynes http://www.kentchemistry.com/links/organic/polymerization.htm

Cracking Breaking of long hydrocarbon chains into smaller ones. Often used on long chain hydrocarbons found in petroleum to make them into more usable fuels. Usually involves a catalyst http://www.kentchemistry.com/links/organic/cracking.htm

Fractional Distillation Separation of a petroleum mixture by differences in Boiling Point temperature. Most compounds in petroleum are non-polar hydrocarbons. Larger chains = stronger VDW = higher BP Smaller chains = weaker VDW = lower BP http://www.kentchemistry.com/links/organic/Fractional.htm

***Esterification*** Dehydration synthesis (water is removed to join molecules) Alcohol + Organic Acid Ester + Water Ester molecules often have nice odors Fats are a type of ester made of glycerol and 3 fatty acid chains http://www.kentchemistry.com/links/organic/esterfication.htm

Saponification (Making Soap) Soap molecules are long molecules that are nonpolar at one end and polar at the other end. Can bring oil and water together Ester + Base Soap + Glycerol http://www.kentchemistry.com/links/organic/saponification.htm