Section 20.1 Saturated Hydrocarbons 1.To understand the types of bonds formed by the carbon atom 2.To learn about the alkanes 3.To learn about structural

Section 20.1

Saturated Hydrocarbons

1. To understand the types of bonds formed by the carbon atom

2. To learn about the alkanes

3. To learn about structural isomers

4. To learn to draw structural formulas

5. To learn to name alkanes and substituted alkanes

6. To learn about the composition and uses of petroleum

7. To learn about the chemical reactions of alkanes

Objectives

Section 20.1


Carbon Chemistry

• Carbon is unusual – Bonds strongly to itself – Forms long chains or rings

• Biomolecule – molecule that functions in maintaining and reproducing life

• Organic compounds – vast majority of carbon compounds – Exceptions – oxides and carbonates

Section 20.1


A. Carbon Bonding

• When carbon has 4 atoms bound to it these atoms have a tetrahedral shape.

Section 20.1


A. Carbon Bonding

Double bond

Triple bond • Sharing of 3 pairs of electrons

• Sharing of 2 pairs of electrons

Section 20.1


B. Alkanes

• Hydrocarbons – compounds composed of carbon and hydrogen– Saturated – all carbon-carbon bonds are single bonds– Unsaturated – containing carbon-carbon multiple bonds

Section 20.1


B. Alkanes

• Alkanes – saturated hydrocarbons

Section 20.1


B. Alkanes

• Normal, straight-chain or unbranched hydrocarbons

• Contain strings or chains of carbon atoms – Representations

Section 20.1


B. Alkanes

Section 20.1


C. Structural Formulas and Isomerism

• Structural isomerism – occurs when 2 molecules have the same atoms but different bonds

Section 20.1


D. Naming Alkanes

• The name for an alkane is based on Greek root with the suffix –ane.

Basic principles

Section 20.1


D. Naming Alkanes

• For branched hydrocarbons use the longest continuous chain for the root name.

Basic principles

Section 20.1


D. Naming Alkanes

• Alkanes missing one H atom can have another hydrocarbon attached at the missing H point.

Basic principles

Section 20.1


D. Naming Alkanes

• Specify the names of substituents by numbering the C atoms starting at the end closest to the branching.

Basic principles

Section 20.1


D. Naming Alkanes

Basic principles

Section 20.1


D. Naming Alkanes

• If a substituent occurs more than once use a prefix to show this.

Basic principles

2,3-dimethylpentane

Section 20.1


D. Naming Alkanes

Section 20.1


E. Petroleum

• Hydrocarbons are an energy resource.

Section 20.1


E. Petroleum

• Petroleum – thick, dark liquid composed mostly of hydrocarbon compounds

• Natural gas – consists mostly of methane, usually associated with petroleum deposits

Section 20.1


F. Reactions of Alkanes

• Combustion – reaction with oxygen

• Substitution – one or more H atoms are replaced with different atoms

Section 20.1


F. Reactions of Alkanes

• Dehydrogenation – one or more H atoms are removed and the product is an unsaturated hydrocarbon

Section 20.2

Unsaturated Hydrocarbons

1. To learn to name hydrocarbons with double and triple bonds

2. To understand addition reactions

3. To learn about the aromatic hydrocarbons

4. To learn to name aromatic compounds

Objectives

Section 20.2


A. Alkenes and Alkynes

• Alkenes – hydrocarbon containing carbon-carbon double bonds

– General formula CnH2n

• Alkynes – hydrocarbons containing carbon-carbon triple bonds

– General formula CnH2n - 2

Section 20.2



Section 20.2


• Addition reactions – new atoms form single bonds to the carbons formerly involved in a double or triple bond

– Hydrogenation – use H2 as the reactant to be added

Reactions of Alkenes

– Halogenation – addition of halogen atoms

• Polymerization – joining of many small molecules to form a large molecule


Section 20.2


B. Aromatic Hydrocarbons

• Aromatic hydrocarbons – cyclic unsaturated hydrocarbons with strong aromas

Section 20.2


B. Aromatic Hydrocarbons

• Benzene – simplest aromatic hydrocarbon

Section 20.2


C. Naming Aromatic Compounds

• Monosubstituted benzenes –

use the substituent name as

a prefix of benzene

Section 20.2



• Disubstituted benzenes – use numbers to indicate the position of substituents and the substituent name as a prefix of benzene

Section 20.2



• Complex aromatic molecules

Section 20.3

Introduction to Functional Groups and Alcohols

1. To learn the common functional groups in organic molecules

2. To learn about simple alcohols and how to name them

3. To learn about how some alcohols are made and used

Objectives

Section 20.3


A. Functional Groups • Functional group – additional atom or groups of atoms

(containing elements in addition to H and C) found on a mostly hydrocarbon molecule

Section 20.3


B. Alcohols

• All alcohols contain the –OH group.

Section 20.3


B. Alcohols

Section 20.3


C. Properties and Uses of Alcohols

• Methanol – starting material for making acetic acid and many

adhesives, fibers and plastics – motor fuel

• Ethanol – Fermentation product

– Fuel additive used to make gasohol

Section 20.3


C. Properties and Uses of Alcohols

• Other alcohols

– Ethylene glycol – automotive antifreeze – Phenol – production of adhesives and plastics

Section 20.4

Additional Organic Compounds

1. To learn about aldehydes and ketones

2. To learn to name aldehydes and ketones

3. To learn about some common carboxylic acids and esters

4. To learn about some common polymers

Objectives

Section 20.4


A. Aldehydes and Ketones

• Carbonyl group – carbon oxygen group found in both aldehydes and ketones

– Ketone – carbonyl group is bonded to two carbon atoms

Section 20.4



– Aldehyde – carbonyl group always appears on the end of the hydrocarbon chain and has at least one H atom bonded to the carbonyl group

Section 20.4



Section 20.4


B. Naming Aldehydes and Ketones

• Aldehydes

– Use the parent alkane name. • Remove the e and replace it with al.

Section 20.4


B. Naming Aldehydes and Ketones

• Ketones

– Use the parent alkane name. • Remove the e and replace it with one. • Use a number to indicate the position of the

carbonyl group in the hydrocarbon chain. – Select the number so that the carbonyl has the lowest

possible number.

Section 20.4


C. Carboxylic Acids and Esters

• Carboxylic acids – contains the carboxyl group

– COOH

• General formula RCOOH • Weak acids in solution

Section 20.4



• To name carboxylic acids

– Use the parent alkane name. • Remove the e and replace it with oic.

Section 20.4



Section 20.4



• Esters – a carboxylic acid reacts with an alcohol to form an ester and a water molecule

– General formula

Section 20.4



• To name esters

– Use the alkyl name from the alcohol followed by the acid name, where the –ic ending is replaced by –ate.

isopropylethanoate

Section 20.4


D. Polymers

• Polymers – large chainlike molecules made from many small molecules called monomers – Simplest polymer – polyethylene– Polyethylene results from addition polymerization.

Section 20.4


D. Polymers

• Condensation polymerization – a small molecule (often water) is released for each addition of a monomer to the polymer chain

• Copolymer – 2 different types of monomers combine to form the chain

– Nylon

Documents

Section 20.1 Saturated Hydrocarbons 1.To understand the types of bonds formed by the carbon atom 2.To learn about the alkanes 3.To learn about structural