Chapter 2Alkanes,2.1Classes of Hydrocarbons,Hydrocarbons,Aromatic,Aliphatic,Hydrocarbons,Aromatic,Aliphatic,Alkanes,Alkynes,Alkenes,Hydrocarbons,Aliphatic,Alkanes,Alkanes are hydrocarbons in which all of the bonds are single bonds.,Hydrocarbons,Aliphatic,Alkenes,Alkenes are hydrocarbons that contain a carbon-carbon double bond.,Hydrocarbons,Aliphatic,Alkynes,Alkynes are hydrocarbons that contain a carbon-carbon triple bond.,Hydrocarbons,Aromatic,The most common aromatic hydrocarbons are those that contain a benzene ring.,2.2Reactive Sites in Hydrocarbons,a structural unit in a molecule responsible for itscharacteristic behavior under a particular set ofreaction conditions,Functional Group,functional group is a hydrogen reaction that takes place is substitution one of the hydrogens is replacedby some other atom or group,Alkanes,functional group is a hydrogen reaction that takes place is substitution one of the hydrogens is replacedby some other atom or group,+ Cl2,+ HCl,Alkanes,alkanesRH alkenesdouble bond alkynestriple bond arenesArH,Functional Groups in Hydrocarbons,2.3The Key Functional Groups,AlcoholsROH Alkyl halidesRX (X = F, Cl, Br, I) Aminesprimary amine: RNH2 secondary amine: R2NH tertiary amine: R3N,Families of organic compoundsand their functional groups,EthersROR NitrilesRC NitroalkanesRNO2 ThiolsRSH,Epoxides,N,Families of organic compoundsand their functional groups,Carbonyl group,Acyl group,R,Many classes of organic compounds contain a carbonyl group,Carbonyl group,Aldehyde,R,H,Many classes of organic compounds contain a carbonyl group,Carbonyl group,Ketone,R,R,Many classes of organic compounds contain a carbonyl group,Carbonyl group,Carboxylic acid,R,OH,Many classes of organic compounds contain a carbonyl group,Carbonyl group,Ester,R,OR,Many classes of organic compounds contain a carbonyl group,Carbonyl group,Amide,R,NH2,Many classes of organic compounds contain a carbonyl group,CnH2n+2,2.4Introduction to Alkanes:Methane, Ethane, and Propane,Methane (CH4) CH4 Ethane (C2H6)CH3CH3 Propane (C3H8)CH3CH2CH3,bp -160C,bp -89C,bp -42C,The Simplest Alkanes,C4H10,2.5Isomeric Alkanes: The Butanes,n-ButaneCH3CH2CH2CH3 Isobutane(CH3)3CH,bp -0.4C,bp -10.2C,2.6Higher n-Alkanes,CH3CH2CH2CH2CH2CH3,n-Pentane,n-Hexane,CH3CH2CH2CH2CH3,CH3CH2CH2CH2CH2CH2CH3,n-Heptane,2.7The C5H12 Isomers,n-Pentane,CH3CH2CH2CH2CH3,Isopentane,(CH3)2CHCH2CH3,Neopentane,(CH3)4C,C5H12,How many isomers?,The number of isomeric alkanes increases as the number of carbons increase. There is no simple way to predict how many isomers there are for a particular molecular formula.,Table 2.3 Number of Constitutionally Isomeric Alkanes,CH41 C2H61 C3H81 C4H102 C5H123 C6H145 C7H169,Table 2.3 Number of Constitutionally Isomeric Alkanes,CH41 C8H1818 C2H61 C9H2035 C3H81 C10H2275 C4H102 C15H324,347 C5H123 C20H42366,319 C6H145 C40H8262,491,178,805,831 C7H169,