Slide 1:Chapter 10.1 HYDROCARBONS


Slide 2:Water forms droplets on a thin film of alkane wax on the skin of the apple.


Slide 3:Biogas, which can come from animal manure is mostly composed of the alkane called methane


Slide 4:Solid long-chain alkanes form a firm layer of wax called the cuticle, over areas of the plant exposed to the air. This protects the plant against water loss, while preventing the leaching of important minerals by the rain


Slide 5:Petroleum Jelly is a semi-solid mixture of hydrocarbons (with carbon numbers mainly higher than 25) Should not be used on Burns, Nasal congestion or dryness, Latex materials


Slide 6:Liquefied Petroleum Gas is composed mainly of propane and butane.


Slide 7:Gas Lighters use butane


Slide 8:Gasoline is primarily composed of pentane and octane


Slide 9:Aerosol Sprays use propane and butane as propellants


Slide 10:Diesel contain nonane and hexadecane


Slide 12:Hydrocarbons Organic Compounds that only contain hydrogen and carbons. Alkanes and Cycloalkanes (carbon-carbon single bond) Alkenes (carbon-carbon double bond) Alkynes (carbon-carbon triple bond)


Slide 13: Hydrocarbons


Slide 14:Alkanes Alkanes are saturated hydrocarbons - Contain only carbon and hydrogen - Bonds are carbon-hydrogen and carbon-carbon single bonds - The general formula for a straight chain alkane CnH2n+2 C4H2(4)+2 C4H10


Slide 15:Nomenclature of Alkanes The names of alkanes are determined by the IUPAC (International Union of Pure and Applied Chemistry) system. end in –ane. with 1-5 carbons in a chain use prefixes as follows:


Slide 16:Nomenclature of Alkanes


Slide 17:Straight Chain and Branched Alkanes Straight-chain alkane: An alkane that has all its carbons connected in a row. Branched-chain alkane: An alkane that has a branching connection of carbons. Constitutional Isomers Compounds which have the same molecular formula but a different arrangement of atoms


Slide 18: Alkyl Groups Alkyl group is a name for an alkane when it is a component of a larger molecule Alkyl Groups with 3 Carbons (n = 3) Propyl group - obtained from removal of a hydrogen from a primary carbon of propane Primary carbon - carbon bonded to only one other carbon atom Isopropyl group - obtained from removal of a hydrogen from a secondary carbon of propane (note arrangement of atoms makes an iso structural unit) Secondary carbon - carbon bonded to only two other carbon atoms


Slide 19: Alkyl Groups Alkyl Groups with 4 Carbons (n = 4) Butyl group - removal of a hydrogen from one primary carbon of butane Isobutyl group - removal of a hydrogen from a primary carbon of isobutane sec-butyl group - removal of a hydrogen from a secondary carbon of butane (sometimes abbreviated s-butyl, for secondary) tert-butyl group - removal of a hydrogen from a tertiary carbon of isobutane (sometimes abbreviated t-butyl, for tertiary) Tertiary carbon - carbon bonded to three other carbon atoms


Slide 20: Alkyl Groups Alkyl Groups with 4 Carbons (n = 4) Butyl group - removal of a hydrogen from one primary carbon of butane Isobutyl group - removal of a hydrogen from a primary carbon of isobutane sec-butyl group - removal of a hydrogen from a secondary carbon of butane (sometimes abbreviated s-butyl, for secondary) tert-butyl group - removal of a hydrogen from a tertiary carbon of isobutane (sometimes abbreviated t-butyl, for tertiary) Tertiary carbon - carbon bonded to three other carbon atoms


Slide 21:Some Common Alkyl Groups


Naming :Naming each name consists of 3 parts prefix indicates position, number, and type of branches indicates position, number, and type of each functional group parent indicates the length of the longest carbon chain or ring suffix indicates the type of hydrocarbon ane, ene, yne certain functional groups


Slide 24:Alkane


Naming Alkanes :25 Naming Alkanes Find the longest continuous carbon chain Number the chain from end closest to a branch if first branches equal distance use next in Name branches as alkyl groups locate each branch by preceding its name with the carbon number on the chain List branches alphabetically do not count n-, sec-, t-, count iso Use prefix if more than one of same group present di, tri, tetra, penta, hexa do not count in alphabetizing


Examples of Naming Alkanes :Examples of Naming Alkanes 2-methylpentane 3-isopropyl-2,2-dimethylhexane


Example – Name the alkane :Example – Name the alkane find the longest continuous C chain and use it to determine the base name since the longest chain has 5 C the base name is pentane


Example – Name the alkane :Example – Name the alkane identify the substituent branches there are 2 substituents both are 1 C chains, called methyl


Example – Name the alkane :Example – Name the alkane number the chain from the end closest to a substituent branch if first substituents equidistant from end, go to next substituent in both substituents are equidistant from the end 1 2 3 4 5 2 4 then assign numbers to each substituent based on the number of the main chain C it’s attached to


Example – Name the alkane :Example – Name the alkane write the name in the following order substituent number of first alphabetical substituent followed by dash substituent name of first alphabetical substituent followed by dash if it’s the last substituent listed, no dash use prefixes to indicate multiple identical substituents repeat for other substituents alphabetically name of main chain 2,4 – dimethyl pentane


Practice – Name the Following :Practice – Name the Following


Practice – Name the Following :Practice – Name the Following 3-ethyl-2-methylpentane


Drawing Structural Formulas :Drawing Structural Formulas draw and number the base chain carbon skeleton add the carbon skeletons of each substituent on the appropriate main chain C add in required H’s 4-ethyl-2-methylhexane


Practice – Draw the structural formula of 4-isopropyl-2-methylheptane :Practice – Draw the structural formula of 4-isopropyl-2-methylheptane


Practice – Draw the structural formula of 4-isopropyl-2-methylheptane :Practice – Draw the structural formula of 4-isopropyl-2-methylheptane


Types of Organic Reactions :Types of Organic Reactions Addition reaction: A general reaction type in which a substance X-Y adds to the multiple bond of an unsaturated reactant to yield a saturated product that has only single bonds.


Slide 42:Elimination reaction: A general reaction type in which a saturated reactant yields an unsaturated product by losing groups from two adjacent carbons.


Slide 43:Substitution reaction: A general reaction type in which an atom or group of atoms in a molecule is replaced by another atom or group of atoms.


Slide 44:Rearrangement reaction: A general reaction type in which a molecule undergoes bond reorganization to yield an isomer.


Alkenes :Alkenes also known as olefins aliphatic, unsaturated C=C double bonds formula for one double bond = CnH2n subtract 2 H from alkane for each double bond trigonal shape around C flat much more reactive than alkanes polyunsaturated = many double bonds


Bonding and Geometryof Two-Carbon Molecules :Bonding and Geometryof Two-Carbon Molecules


Structural Comparison of Five Carbon Molecules :Structural Comparison of Five Carbon Molecules


Properties of Alkenes and Alkynes :Properties of Alkenes and Alkynes Like the alkanes, alkenes and alkynes are: Nonpolar; insoluble in water; soluble in nonpolar organic solvents; less dense than water Flammable; nontoxic Unlike the alkanes: Alkenes display cis–trans isomerism when each double-bond carbon atom has different substituents Alkenes and alkynes are chemically reactive at the multiple bond


Physical Properties of Alkenes :Physical Properties of Alkenes


Alkynes :Alkynes also known as acetylenes aliphatic, unsaturated CºC triple bond formula for one triple bond = CnH2n-2 subtract 4 H from alkane for each triple bond linear shape more reactive than alkenes


Alkynes :Alkynes ethyne = acetylene propyne


Physical Properties of Alkynes :Physical Properties of Alkynes


Naming Alkenes and Alkynes :Naming Alkenes and Alkynes change suffix on main name from -ane to -ene for base name of alkene, or to -yne for the base name of the alkyne number chain from end closest to multiple bond number in front of main name indicates first carbon of multiple bond


Name the Alkene :Name the Alkene find the longest, continuous C chain that contains the double bond and use it to determine the base name since the longest chain with the double bond has 6 C the base name is hexene


Name the Alkene :Name the Alkene identify the substituent branches there are 2 substituents one is a 1 C chain, called methyl the other one is a 2 C chain, called ethyl


Name the Alkene :Name the Alkene number the chain from the end closest to the double bond then assign numbers to each substituent based on the number of the main chain C it’s attached to


Name the Alkene :Name the Alkene write the name in the following order substituent number of first alphabetical substituent – substituent name of first alphabetical substituent – use prefixes to indicate multiple identical substituents repeat for other substituents number of first C in double bond – name of main chain 3–ethyl– 4–methyl– 2–hexene


Practice – Name the Following :Practice – Name the Following


Practice – Name the Following :Practice – Name the Following 3,4-dimethyl-3-hexene 1 2 3 4 5 6


Name the Alkyne :Name the Alkyne find the longest, continuous C chain that contains the triple bond and use it to determine the base name since the longest chain with the triple bond has 7 C the base name is heptyne


Name the Alkyne :Name the Alkyne identify the substituent branches there are 2 substituents one is a 1 C chain, called methyl the other one is called isopropyl


Name the Alkyne :Name the Alkyne number the chain from the end closest to the triple bond then assign numbers to each substituent based on the number of the main chain C it’s attached to


Name the Alkyne :Name the Alkyne write the name in the following order substituent number of first alphabetical substituent – substituent name of first alphabetical substituent – use prefixes to indicate multiple identical substituents repeat for other substituents number of first C in double bond – name of main chain 4–isopropyl– 6–methyl– 2–heptyne


Practice – Name the Following :Practice – Name the Following


Practice – Name the Following :Practice – Name the Following 3,3-dimethyl-1-pentyne 1 2 3 4 5


Slide 68: Naming Alkenes and Alkynes Using IUPAC Nomenclature Example 11.1 Name the following alkene and alkyne using IUPAC nomenclature 3-methyl-4-propyl-3-octene 2,2-dimethyl-3-hexyne


Molecules With More Than One Double Bond :Molecules With More Than One Double Bond Alkenes having more than one double bond: 2 double bonds = alkadiene 3 triple bonds = alkatriene Same rules for alkynes


Naming Haloalkenes :Naming Haloalkenes Double or triple bonds take precedence over a halogen or alkyl group 2-Chloro-2-butene If 2 or more halogens, indicate the position of each


Cycloalkanes :Cycloalkanes Cycloalkane: One or more rings of carbon atoms. 6 C 3 C 4 C 5 C


Cycloalkanes :Cycloalkanes


Cycloalkanes :Cycloalkanes


Slide 74: Naming Cycloalkanes Using IUPAC Nomenclature Example 11.2 Name the following cycloalkanes using IUPAC nomenclature 4-chlorocyclohexane 3-methylcyclopentene


10.5 Reactions of Alkanes :10.5 Reactions of Alkanes Alkanes, cycloalkanes, and other hydrocarbons can be: Oxidized (by burning) in the presence of excess molecular oxygen, in a process called combustion Reacted with a halogen (usually chlorine or bromine) in a halogenation reaction


Alkane Reactions :Alkane Reactions The majority of the reaction of alkanes are combustion reactions Complete CH4 + 2O2 CO2 + 2H2O Complete combustion produces Carbon dioxide and water Incomplete 2CH4 + 3O2 2CO + 4H2O Incomplete combustion produces Carbon monoxide and water Carbon monoxide is a poison that binds irreversibly to red blood cells


Halogenation :Halogenation Halogenation is a type of substitution reaction, a reaction that results in a replacement of one group for another Products of this reaction are: Alkyl halide or haloalkane Hydrogen halide This reaction is important in converting unreactive alkanes into many starting materials for other products Halogenation of alkanes ONLY occurs in the presence of heat and/or light (UV)


Reactions Involving Alkenes and Alkynes :Reactions Involving Alkenes and Alkynes There are two kinds of reactions typical of alkenes: Addition: two molecules combine to give one new molecule Redox: oxidation and reduction The two classes are not always mutually exclusive


Addition: General Reaction :Addition: General Reaction A small molecule, AB, reacts with the pi electrons of the double bond The pi bond breaks and its electrons are used to bond to the A and B pieces Some additions require a catalyst


Types of Addition Reactions :Types of Addition Reactions Symmetrical: same atom added to each carbon Hydrogenation - H2 (Pt, Pd, or Ni as catalyst) Halogenation - Br2, Cl2 Unsymmetrical: H and another atom are added to the two carbons Hydrohalogenation - HCl, HBr Hydration - H2O (requires strong acid catalyst e.g., H3O+, H2SO4, H3PO4) Self-addition or polymerization


Hydrogenation: Addition of H2 :Hydrogenation: Addition of H2 Hydrogenation is the addition of a molecule of hydrogen (H2) to a carbon-carbon double bond to produce an alkane The double bond is broken Two new C-H bonds result Platinum, palladium, or nickel is required as a catalyst Heat and/or pressure may also be required


Halogenation: Addition of X2 :Halogenation: Addition of X2 Halogenation is the addition of a molecule of halogen (X2) to a carbon-carbon double bond to produce an alkane The double bond is broken Two new C-X bonds result Reaction occurs quite readily and does NOT require a catalyst Cl and Br are most often the halogen added


Bromination of an Alkene :Bromination of an Alkene Left beaker contains bromine, but no unsaturated hydrocarbon Right beaker contains bromine, but reaction with an unsaturated hydrocarbon results in a colorless solution


Unsymmetrical Addition :Unsymmetrical Addition Two products are possible depending how the 2 groups (as H and OH) add to the ends of the pi bond The hydrogen will add to one carbon atom The other carbon atom will attach the other piece of the addition reagent OH (Hydration) Halogen (Hydrohalogenation)


Hydration :Hydration A water molecule can be added to an alkene The addition of a water molecule to an alkene is called hydration Presence of strong acid is required as a catalyst Product resulting is an alcohol


Markovnikov’s Observation :Markovnikov’s Observation Dimitri Markovnikov (Russian) observed many acid additions to C=C systems He noticed that the majority of the hydrogen went to a specific end of the double bond He formulated an explanation


Markovnikov’s Rule :Markovnikov’s Rule When an acid adds to a double bond -the H of the acid most often goes to the end of the double bond, which had more hydrogens attached initially H-OH H-Cl H-Br


Hydrohalogenation :Hydrohalogenation An alkene can be combined with a hydrogen halide such as HBr or HCl The reaction product is an alkyl halide Markovnikov’s Rule is followed in this reaction


Hydration of Alkynes :Hydration of Alkynes Hydration of an alkyne is a more complex process The initial product is not stable Enol produced – both an alkene and an alcohol Product is rapidly isomerized Final product is either Aldehyde Ketone


Addition Polymers of Alkenes :Addition Polymers of Alkenes Polymers are macromolecules composed of repeating units called monomers Polymers can be made up of thousands of monomers linked together Many commercially important materials are addition polymers made from alkenes and substituted alkenes Addition polymers are named for the fact that they are made by the sequential addition of the repeating alkene monomer


Slide 91: Writing Equations for the Hydrogenation of Alkenes Example 11.6 Write a balanced equation showing the hydrogenation of (a) 1-pentene and (b) trans-2-pentene.


Slide 92:Writing Equations for the Halogenation of Alkenes Example 11.7 Write a balanced equation showing (a) the chlorination of 1-pentene and (b) the bromination of trans1-butene. + +


Slide 93:Writing Equations for the Hydration of Alkenes Example 11.8 Write an equation showing all the products of the hydration of 1-pentene.


Slide 94:Writing Equations for the Hydrohalogenation of Alkenes Example 11.9 Write an equation showing all the products of the hydration of 1-pentene.


Slide 95:Naming Derivatives of Benzene Example 11.10 Name the following compounds using the IUPAC Nomenclature System. 2-chlorotoluene 4-nitrophenol 3-ethylaniline


Slide 96:Naming Derivatives of Benzene Example 11.11 Name the following compounds using the common system of nomenclature. ortho-chlorotoluene para-nitrophenol meta-ethylaniline