8/9/2019 Organic Chemistry Introduction >>Examville.com Study Guides Section

http://slidepdf.com/reader/full/organic-chemistry-introduction-examvillecom-study-guides-section 1/19

Introduction to OrganicChemistry

8/9/2019 Organic Chemistry Introduction >>Examville.com Study Guides Section

http://slidepdf.com/reader/full/organic-chemistry-introduction-examvillecom-study-guides-section 2/19

Contents

Nomenclature and IsomerismPetroleum and Alkanes

Alkenes and EpoxyethaneHaloalkanesAlcohols

8/9/2019 Organic Chemistry Introduction >>Examville.com Study Guides Section

http://slidepdf.com/reader/full/organic-chemistry-introduction-examvillecom-study-guides-section 3/19

Nomenclature and Isomerism

The study of the compound of carbon iscalled organic chemistry.

Groups of carbon compounds with thesame functional group are calledhomologous seriesOrganic compounds are named accordingto their longest carbon chain.

Number of Catoms

1 2 3 4 5 6

Prefix Meth- Eth- Pro- But- Pent- Hex-

8/9/2019 Organic Chemistry Introduction >>Examville.com Study Guides Section

http://slidepdf.com/reader/full/organic-chemistry-introduction-examvillecom-study-guides-section 4/19

NomenclatureHomologous Series General Formula Name Functional group

Alkanes CnH 2n+2 -ane C ±H

Alkenes CnH2n -ene C=C

Haloalkanes chloro -, bromo- etc ±Cl or ±Br

Alcohols CnH2n+1 OH -ol ±OH Aldehyde -al

Ketones -one C=O

Carboxylic Acids CnH 2n CO 2H -oic

Esters -oate

±CO

H

±CO

O±C

±CO

OH

8/9/2019 Organic Chemistry Introduction >>Examville.com Study Guides Section

http://slidepdf.com/reader/full/organic-chemistry-introduction-examvillecom-study-guides-section 5/19

IsomerisationBoth of the following have four carbon atoms and ten hydrogen atoms theyare called isomers

CH 3 ±CH 2 ±CH 2 ±CH 3 CH 3 ±CH ±CH 3

CH 3

Butane 2-Methyl propane

The number 2 indicates that the methyl group is attached to the second carbon.Carbons are always number so that the lowest numbers appear in the name.

This type of isomerism is called structural isomerismPositional isomers have functional groups at different positions along the chainFunctional group isomers have different functional groups but have the same

molecular formulae, such as acids and esters

8/9/2019 Organic Chemistry Introduction >>Examville.com Study Guides Section

http://slidepdf.com/reader/full/organic-chemistry-introduction-examvillecom-study-guides-section 6/19

Petroleum and Alkanes

PetroleumCombustionPollution

8/9/2019 Organic Chemistry Introduction >>Examville.com Study Guides Section

http://slidepdf.com/reader/full/organic-chemistry-introduction-examvillecom-study-guides-section 7/19

PetroleumPetroleum is another name for crude oil, it is a mixture of hydrocarbons.The hydrocarbons in crude oil all have different boilingpoints, this property allows them to be separated by a

process call fractional distillation.Fractional distillation produces more long chainhydrocarbons than the market requires. They are madeinto shorter more useful molecules by a process calledcracking.

Thermal cracking splits the bonds in the hydrocarbon bya free radical process this uses a lot of energy becauseof the high temperatures used.Zeolite catalysts can be used to lower the temperature of the cracking process. It proceeds via ionic intermediates.

8/9/2019 Organic Chemistry Introduction >>Examville.com Study Guides Section

http://slidepdf.com/reader/full/organic-chemistry-introduction-examvillecom-study-guides-section 8/19

Combustion

In excess oxygen alkanes burn accordingto the following equation:

CnH2n+2 +(1.5n+0.5)O 2 nCO 2 +(n+1)H 2OThis is called complete combustion,however if there is in sufficient oxygenpresent incomplete combustion can occur.CnH2n+2 +(n+0.5)O 2 nCO +(n+1)H 2OWith even less oxygen soot is formed.

8/9/2019 Organic Chemistry Introduction >>Examville.com Study Guides Section

http://slidepdf.com/reader/full/organic-chemistry-introduction-examvillecom-study-guides-section 9/19

Pollution

Many pollutants are formed by the combustion of fossilfuels. These include soot and carbon monoxide formedby the incomplete combustion of hydrocarbons.Besides making every thing look dirty carbon particulatesin the atmosphere cause breathing problems in thosewho are susceptible.Carbon monoxide interferes with the blood¶s ability tocarry oxygen and in severe case can lead to death.Other harmful gases include: ± sulphur dioxide which is formed by the oxidation of impurities in

fossil fuels

± and nitrogen oxides which are formed atmospheric nitrogen isoxidised during the combustion process.Both of these species react with rain water to form acidrain.

8/9/2019 Organic Chemistry Introduction >>Examville.com Study Guides Section

http://slidepdf.com/reader/full/organic-chemistry-introduction-examvillecom-study-guides-section 10/19

Alkenes and EpoxyethaneAlkenes are unsaturated. This means that theydo not have the maximum possible number of hydrogen atoms.The double bond in in alkenes is comprised of acovalent bond and a pi bond. The pi bond haselectron density above and below the covalentbond and is weaker than a covalent bond.Because of the weaker second bond alkenes

are more reactive than alkanes.There is no rotation around the double bond, thiscauses alkenes to have a planar shape.

8/9/2019 Organic Chemistry Introduction >>Examville.com Study Guides Section

http://slidepdf.com/reader/full/organic-chemistry-introduction-examvillecom-study-guides-section 11/19

R eactions of Alkenes

H H ±C ±C ±

H H

Br Br

±C ±C ±

H Cl

±C ±C ±

H OH

±C ±C ±

alkane

C=C

+H2 catalyst

Heat & pressure

+Br 2 +HCl

+steam &catalyst

n

Catalyst &heat

R emember in thepresence of alkenesbromine water decolourises

8/9/2019 Organic Chemistry Introduction >>Examville.com Study Guides Section

http://slidepdf.com/reader/full/organic-chemistry-introduction-examvillecom-study-guides-section 12/19

Epoxyethane

Epoxyethane is produced from etheneand air or oxygen in the presence of asilver catalyst.The 3-membered ring is strained andresults in high reactivity.Epoxyethane is industrially important

because it is hydrolysed to produceethane-1,2 diol which is then used in theproduction of antifreeze and polyesters.

O

CH2

CH2

8/9/2019 Organic Chemistry Introduction >>Examville.com Study Guides Section

http://slidepdf.com/reader/full/organic-chemistry-introduction-examvillecom-study-guides-section 13/19

HaloalkanesHaloalkanes contain polar bonds. This is because thehalogen is more electronegative than the carbon.This results in the carbon atom being slightly positive andattractive to electron rich species.R

eactions resulting from this type of attraction are callednucleophilic substitution.

C Br : CN -H-H+

The carbon atom of the CN - iondonates a pair of electrons tothe haloalkane and the C ±Br breaks with loss of a bromideion. A new C ±CN bond isformed.

8/9/2019 Organic Chemistry Introduction >>Examville.com Study Guides Section

http://slidepdf.com/reader/full/organic-chemistry-introduction-examvillecom-study-guides-section 14/19

Elimination

On heating bromoethane with a strongbase dissolved in ethanol, hydrogenbromide is eliminated and ethene isformed:CH3CH 2Br CH 2=CH 2 + HBr KOH/ethanol

8/9/2019 Organic Chemistry Introduction >>Examville.com Study Guides Section

http://slidepdf.com/reader/full/organic-chemistry-introduction-examvillecom-study-guides-section 15/19

Alcohols

C OH

C

C

CC OH

H

H

C C OH

H

C

C

Primary Secondary Tertiary

Alcohols are classified according to the number of carbonatoms bonded to the carbon atom adjacent to the OHgroup.

8/9/2019 Organic Chemistry Introduction >>Examville.com Study Guides Section

http://slidepdf.com/reader/full/organic-chemistry-introduction-examvillecom-study-guides-section 16/19

Manufacture of Alcohols

Alcohol for human consumption isproduced by natural fermentation. Yeastsproduce enzymes which catalyse thereaction called zymases.Industrially it cheaper to form ethanol for solvent by the hydrolysis of ethene.

It is cheaper to obtain ethanol in thismanner because it is produced in acontinuous process

8/9/2019 Organic Chemistry Introduction >>Examville.com Study Guides Section

http://slidepdf.com/reader/full/organic-chemistry-introduction-examvillecom-study-guides-section 17/19

R eactions of Alcohols

Oxidation of primary alcohols produces analdehyde.Aldehydes produce a silver mirror with Tollen¶s

reagentSecondary and tertiary alcohols produceketones upon oxidation these do not give asilver mirror with ketones.

Heating alcohols with sulphuric or phosphoricacid causes them to eliminate water andproduce alkenes

8/9/2019 Organic Chemistry Introduction >>Examville.com Study Guides Section

http://slidepdf.com/reader/full/organic-chemistry-introduction-examvillecom-study-guides-section 18/19

8/9/2019 Organic Chemistry Introduction >>Examville.com Study Guides Section

http://slidepdf.com/reader/full/organic-chemistry-introduction-examvillecom-study-guides-section 19/19

T ry Examville.com for FREE .

All you need as an email address to join Examville.

Find out more at : www.Examville.com

Follow us at twitter: www.twitter.com/examville

Became a fan of Examville: http : //www.facebook.com/pages/Examvillecom/117840882461?v=info

Examville Blog: www.examville.net/wordpress