Download Organic Chemistry: Properties and Nomenclature of Alkanes and Aromatics - Prof. Roman E. B and more Study notes Biology in PDF only on Docsity! Organic Chemistry 1. Study of carbon or organic compounds 2. Carbon major element in biological compounds Organic vs Inorganic 1. Organic- all have carbon, covalent bonds, low melting & boiling points, most are nonpolar & nonelectrolytes 2. Inorganic- Metal salts & oxides, ionic or polar bonds, high melting & boiling points, most are polar & electrolytes Alkenes 1. At least one double C=C 2. Unsaturated 3. Examples- C2H4, ethene (ethylene); C3H6, propene; C4H8, 1-butene or 2-butene . . . Alkynes 1. At least one triple C C bond 2. Unsaturated 3. Examples- C2H2, ethyne (acetylene); C3H4, propyne; C4H6, 1-butyne or 2-butyne . . . Aromatics 1. One or more benzene rings, 6-C ring with alternating single & double bonds 2. Example- C6H6, benzene; naphthalene, C10H8 Structural Formula, Alkanes 1. CH4 2. C2H6 3. C3H8 4. C4H10 . . . Alkane Properties 1. Physical Properties 2. Chemical Properties Physical Properties 1. CH4 to C4H10 are gases, C5H12 to C17H36 are liquids, C18H38 and above are waxy solids at STP 2. All alkanes are nonpolar 3. Liquid alkanes are less dense than water Alkyl Examples 1. Methyl 2. Ethyl 3. Propyl . . . Alkane Nomenclature, steps 1-3 1. Longest unbranched chain is parent chain 2. End nearest first side chain is C1; if two side chain carbons are same distance from ends, assign lowest number in alphabetical order 3. Number & name each side chain attached to parent chain Alkane Nomenclature, step 4 1. Write number & name of side chains in front of parent chain a. Use prefixes if identical side chains, commas separate numbers, dashes separate names & numbers b. Alphabetize side chains, dashes separate names & numbers Nomenclature Example 1, step 3 3. Number & name side chains 2-methyl 3-methyl Nomenclature Example 1, step 4 4. Write out full name 2,3-dimethylpentane Nomenclature Example 2, step 1 1. Name parent chain hexane Nomenclature Example 2, step 4 4. Write out full name 4-ethyl-2-methylhexane Alkane Name to Structure
1. 2,3-dimethylhexane
ga HY
HEF
ee |
2. 2,3,3-trimethylhexane
awe
Structural Isomers 1. Compounds with identical molecular formula but different structure, therefore different properties C4H10 Aromatics 1. Cyclic compounds with hybrid or resonance single & double bonds 2. Benzene most common or Aromatic Nomenclature 1. Name parent ring, add group name as prefix 2. Methylbenzene (toluene), chlorobenzene 3. Ortho, meta, para or numbered Aromatic Examples
one Cl
nn
nn
1,2-dimethylbenzene 1-chloro-3-methylbenzene
(o-dimethylbenzene)
