1

Chemistry 2202

Unit II: Organic Chemistry Name:____________________

What is Organic Chemistry?

- the study of the compounds that contain the element Carbon

- all living organisms contain a wide variety of organic compounds

- cells - though composed of seventy to ninety percent water, most of the rest of the

cell is composed of carbon based material

- DNA, proteins, carbohydrates, etc.

Carbon accounts for the endless diversity in biological organisms.

- fossil fuels

- food / drink

- paper

- clothes

- soap / perfume

There is such a large number, and variety, of organic compounds, more than 10 million, there is a

special naming system used to organize, classify and name them.

Chemical Compounds

Molecular Compounds

- contains only non-metallic elements

Ionic Compounds

Inorganic Compounds

Any compound that

does not contain

carbon

The carbon oxides,

such as CO2 and CO,

along with polyatomic

ions containing carbon,

such as CO32-

and

HCO3-, however, are

also considered

inorganic.

Inorganic

Compounds

Any compound

that does not

contain carbon

Organic

Compounds

Any compound

that does contain

carbon atoms.

Exceptions

include carbon

oxides, such as

CO2 and CO,

and polyatomic

(complex) ions

containing

carbon.

2

Organic Compounds

- historically thought to only come from living or once-living sources (vital source)

- 1828 - Frederich Wohler produced, by accident, the first organic compound named

urea - (a substance found naturally in the urine of animals) from an inorganic

compound (ammonium cyanate)

- now chemists invent more than 250,000 new organic compounds every year

- there are millions of organic compounds and they are organized and categorized

based on chemical and physical properties. Naming and classifying these compounds

does prove difficult, however, as there is more than one classification and naming

system.

Inorganic Compounds

- historically thought to only come from non-living materials such as minerals

- now defined as any molecule that does NOT contain C (some exceptions include the

poly-atomic ions that contain carbon atoms; Eg. CO3, HCO3-, SCN

–, etc.)

Examples of Organic Compounds

- Natural:

- proteins, lipids, carbohydrates, cellulose

- fossil fuels (Ex: gas, oil, coal)

- natural fibers ( cotton, wool, silk, paper)

- Manufactured (Synthetic):

- pesticides

- CFC’s

- medicine (ex: painkillers, antibiotics, insulin)

- polyesters/plastics

- artificial sweeteners/flavouring (sugar twin, vanilla extract)

- perfume, cosmetics, soap, detergent

- paints, varnish TNT

Classifying Organic Compounds - the system for classifying these compounds is based on

- Chemical Properties - how these substances react with other substances

- Physical Properties - MP/BP

- Solubility

- Bonding/Structure

- Functional Group - key atom arrangement within a molecule

- reactions take place at functional group

- ex. - ethanol - C2H5OH or CH3-CH2-OH

- OH is the functional group. It tells us that ethanol is an

alcohol Questions pg. 323 #’s 1, 5

3

Chemistry 2202

Homework Name:_____________________

Questions pg. 323 #’s 1, 5

1. a.

b.

c.

5. a.

b.

c.

d.

e.

f.

g.

h

4

Why Carbon?

Why the special consideration for carbon?

Considering that carbon makes up only 0.02 % elements in the earth’s crust. What makes

these molecules so unique?

1. It has high bonding capacity (4 bonding e-).

2. It can form single, double, and triple bonds. It can form chains, branches, rings,

spheres, sheets, tubes, etc.

3. C to C bonds are very stable.

4. It can bond with other elements (ex: H, N, O, halogens).

5. There are several times more carbon based compounds that there are compounds of

all the other elements combined.

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The following diagram represents the basic classification system for carbon compounds - as studied in

Chemistry 2202.

Hydrocarbon Derivatives compounds that contain carbon,

hydrogen and other atoms such as O,

N, S, etc.

Alkanes

normal

branched

cyclo

Alcohol Ketone

Alkenes

normal

branched

cyclo

Amine Ester

Alkynes

normal

branched

cyclo

Amide

Ether

Alkyl Halide Aldehyde

Carboxylic Acid

(Organic Acid)

Organic Compound

Pure Hydrocarbons

compounds that contain

carbon and hydrogen atoms

only

Aliphatic Aromatic

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Structural Formulas

- we use four types of formulas to represent organic compounds. Using the formula C5H12 we

consider the four types.

Complete Structural Formula

- shows all atoms and bonds

Skeleton Structural Formula

- shows all atoms and bonds

Condensed Structural Formula

- shows C-C bonds but not C-H bonds

Line Structural Formula

- shows only C-C bonds as a zigzag

- each corner is a C

Your Turn! Draw complete, skeletal, condensed and line structural diagrams forC3H8, C6H14

Complete Structural

Formula

Condensed Structural

Formula

Line Structural

Formula C3H8

C3H8 C3H8

C6H14

C6H14 C6H14

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Pure Hydrocarbons - compounds containing only C and H atoms

- ex: coal, oil, gas, plastic, polyester

- 2 types - aliphatic and aromatic

Aliphatic

- hydrocarbons in which carbon atoms form: - straight, continuous chain (with or without branches)

- cyclic (ring) structure

- ex: fats, oils

Organic Compounds

Hydrocarbon Derivative Pure Hydrocarbon

Aliphatic Aromatic

8

Naming Organic Compounds

There are special prefixes that indicate the number of C atoms in an organic compound.

Note: Only the first four prefixes are new to you.

Number of Carbon

Atoms

Prefix

1 meth

2 eth

3 prop

4 but

5 pent

6 hex

7 hept

8 oct

9 non

10 dec

Homologous Series

- a series formed when a group of compounds differs by a “unit”

- alkanes are such a series b/c each molecule differs by a “CH2" unit

- propane (C3H8 ) and butane (C4H10) are homologs because they differ in numbers of

carbon atoms by only one.

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Aliphatic Hydrocarbons

- there are three types of aliphatic type pure hydrocarbons.

1. Alkane

- all C-C single bonds

- normal (straight chain)

- branched

- cyclo

2. Alkene

- at least one C=C double bond

- normal(straight chain)

- branched

- cyclo

3. Alkyne

- at least one C C triple bond

- normal(straight chain)

- branched

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1. Alkanes - basic formula is CnH2n+2

- all single C-C bonds

- Example - Methane - simplest alkane

Note: Alkanes are referred to as saturated

hydrocarbons because there are no multiple bonds. Each

carbon has the maximum number of hydrogens attached.

Try these: C4H?

What is its formula?

# of H = 2(4) + 2 = 10

C4H10

C4H10 – butane

C?H14

14 = 2n + 2

12 = 2n

n = 12/2 = 6

The formula is C6H14

C6H14 – hexane

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Alkane Properties

- Boiling and Melting point - increases as # C increases

Alkane Boiling Point (oC)

CH4 -161

C2H6 -88.5

C3H8 -42.0

C4H10 0.5

- State at STP - CH4 to C4H10

- gas Ex: natural gas, petrochemicals

- C5H12 to C17H36

- liquid Ex: C5-C10 is gasoline, C12-C13 is kerosene, jet

fuel, diesel

- greater than C17H36

– solid Ex: C20 and higher is grease, paraffin wax, tar

- Solubility - hydrocarbons generally are tetrahedral shape

- hydrocarbons generally non-polar

- they DO NOT dissolve in polar water

- Reactivity - Alkanes are sometimes inert b/c H-C bonds and C-C bonds

very are generally stable.

- They do react with halogens (substitution) and oxygen

(combustion).

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Naming Alkanes

Steps 1. Count # of C in a chain or formula. 2. Select prefix that represents that number of carbons.

3. Finish prefix with –ane

Structural Formula Name

CH4

CH3 – CH2 – CH3

CH3 – CH2 – CH2 – CH2 – CH2 - CH3

CH3 – CH2 – CH2 – CH3

CH2 – CH2 – CH2 – CH2 – CH2 – CH2 – CH3

CH2 – CH2 – CH2 – CH2 – CH2 – CH2 – CH2 – CH3

CH3 – CH3

CH3 – CH2 – CH2 – CH2 – CH3

13

Branched Chain Alkanes - any alkane with one or more branches (alkyl group) coming off the main chain

structure

- alkyl group never on the end of a chain

- Same prefixes for identifying branches (Ex: meth- CH3 branch)

Naming Branched Chain Alkanes

1. Name the parent chain (longest C chain).

2. Number the C atoms in the parent chain, starting with the C closest to branch(es).

3. Identify branch using prefixes and add -yl on the end.

4. Identify location of branch on chain.

5. If there are two or more ‘same type’ branches use molecular prefixes (di, tri, tetra) to indicate

number.

6. Place branch names in alphabetical order.

7. Write name in this format:

(#location) - (branch names)(parent chain)

NOTE: Dashes separate numbers and words

Commas separate numbers

Examples

Structural Formula Name

CH3

CH3 – CH2 – CH2 – CH2 – CH3

CH2 – CH2 – CH2 – CH2 – CH2 – CH2 – CH3

CH3

CH2 – CH2 – CH2 – CH2 – CH2 – CH2 – CH3

CH3

CH3 – CH2 – CH2 – CH – CH - CH3

CH2

CH3

Questions page 336 / 337 #’s 5, 6, 7

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Questions page 336 / 337 #’s 5, 6, 7

5. a.

b.

c.

d.

e.

6. a.

b.

c.

7. a.

b.

c.

15

Drawing Branched Chain Alkanes 1. Draw chain of C atoms according to the parent name.

2. Attach all branches.

3. Add enough H atoms so each C has 4 bonds.

Examples:

2 - methyl propane

2, 2 - dimethyl - 4, 5, 7 – tripropyldecane

3,3 - dimethylhexane

Q’s Page 338 #’s 8, 9, 10, 11

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Chemistry 2202

Homework Questions Name:_____________________

Q’s Page 338 #’s 8, 9, 10, 11

8. a.

b.

c.

9. a.

b.

c.

10. a.

b.

c.

d.

11. a.

b.

c.

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Cycloalkanes - basic formula is Cn H2n

- carbon chains with a ‘ring’ type structure

- may or may not have branches

Naming Cycloalkanes - count the number of carbon atoms and name the same as continuous chain

alkanes.

- if compound is a ring type structure add prefix ‘cyclo’ to alkane name.

Examples

Structural Formula Compound Name

cyclopropane

cyclopentane

cyclohexane

cyclooctane

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Chemistry 2202

Organic Chemistry: Aliphatic Hydrocarbons Name:__________________

Name the following alkyl groups (branches).

1. - CH3 ___________________________________

2. - CH2 - CH2 - CH3 ___________________________________

3. - CH2 - CH2 - CH2 -CH3 ___________________________________

4. - CH2 –CH2 –CH2 –CH2 -CH3 ___________________________________

5. - CH2 – CH2 –CH2 –CH2 –CH2 -CH3 ___________________________________

6. - CH2 –CH2 –CH2 –CH2 –CH2 –CH2 -CH3 ___________________________________

Name the following branched chain alkanes.

Structural Formula Name

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Draw the condensed and line structural formulas for each of the following.

Name Condensed SF Line SF

2-methylpropane

3,3-dimethylhexane

4-ethyl-2-methylpentane

3,4,5-trimethyloctane

3-ethyl-4,4-dimethyloctane

1,2 - diethylcyclopentane 1,2,5 - trimethylcyclooctane 1-ethyl-2,3-dimethylcyclopropane ethylmethylpropylcyclopropane 1-ethyl-3-propylcyclobutane

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Chemistry 2202

Organic Chemistry: Aliphatic Hydrocarbons Name:__________________ Aliphatic Hydrocarbons_4

Complete the Following: 1

2

3

4

5

6

7

8

9

10

Draw the following: Alkane

Skeletal SF

Condensed SF

Line SF

cyclopentane

3,3 - dimethyl octane

heptane

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Chemistry 2202

Organic Chemistry: Aliphatic Hydrocarbons Name:__________________ (Aliphatic Hydrocarbons_5)

Name the following: 1

2

3

4

5

6

7

8

9

10

Draw the following: Alkane

Skeletal SF

Condensed SF

Line SF

octane

2,3 - dimethyl octane

3 - hexane

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2. Alkenes - basic formula: CnH2n

- hydrocarbons that have at least one C to C double bond

- more reactive than alkanes b/c of double bond

- these carbon structures are also referred to as unsaturated hydrocarbons

- they do not have the maximum number of hydrogens attached to each carbon.

- the double bond prevents the compound having the maximum number of hydrogen

atoms.

- Example:

Ethene: C2H6 - simplest alkene

- used to treat green fruit to make it ripen faster

- in the past used as anesthetic

- used as starting material for polymers such as polyethene

which is used for plastics, toys, household products, industrial

products, etc.

Note: When drawing structural formulas for alkenes it is important to remember that

each carbon atom must have four bonds.

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Naming Alkenes

1. Count longest chain of C atoms that contains the double bond.

2. Number this chain, counting from the end that is closest to the double bond.

3. Locate double bond and indicate its location in the name with the number of carbon the bond is after.

4. Complete the name using the appropriate prefix plus “ene.”

Examples

Structural Formula Compound Name

CH2 CH2

1-ethene or ethene

CH2 = CH – CH2 – CH3

1-butene or butene

CH3 - CH = CH – CH3

2-butene

CH3 - CH2 - CH = CH – CH2 – CH3

3-hexene

CH2 = CH – CH2 – CH2 – CH3

1 - pentene

CH3 - CH = CH – CH2 – CH2 – CH3

2 - hexene

CH3 – CH2 – CH2 – CH = CH – CH2 – CH2 – CH2 - CH3

4 - nonane

CH2 – CH2 – CH = CH – CH2 – CH2 – CH2 - CH3

3 - octane

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Naming Branched Chain Alkenes

The method of naming is similar to the alkanes except you count from the end of the carbon

molecule that is closest to the double bond, not the end closest to the branch.

Examples

Structural formula Compound Name

3,4-dimethyl-2-hexene

3-methyl-2-pentene

2-ethyl-4-methyl-1-hexene

2,3-dimethyl-2-butene

4-ethyl-3-octene

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Cycloalkenes

- basic formula is CnH2n - 2

- ____________________________________________________________________

Naming Cycloalkenes

1. Count the number of carbon atoms and name the same as continuous chain alkenes.

2. If compound is a ring type structure, add prefix ‘cyclo’ to alkane name.

Examples

Structural Formula Compound Name

cyclopentene

cyclopropene

cyclooctene

2-ethyl-1-methyl cyclohexene

1-methyl cyclopropene

1-ethyl-3-methyl cyclobutene

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Chemistry 2202 Organic Chemistry: Aliphatic Hydrocarbons Name:__________________ (Aliphatic Hydrocarbons_7) 1. Name the Following: 1

2

3

4

CH3 - CH = C – CH2 – CH2 – CH3

CH2

CH2

CH3

5

CH3

CH3 - CH - CH – C – CH2 – CH3

CH3 CH - CH2 - CH3

6

7

8

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2. Draw the following: Alkene/Alkyne

Skeletal SF

Condensed SF

Line SF

2-octene

4-ethyl-3-methyl-1-

heptene

3-hexene

cyclopropene

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Isomers

- substances with same molecular formula but different structures

- Examples:

- C10H22 - 75 isomers

- C20H42 - 366 319 isomers

- C30H62 - 4,111, 646, 763 isomers

Pure Hydrocarbon Isomers

Pure Hydrocarbon type Compound Formula

Alkanes CnH 2n + 2

Alkenes CnH2n

Alkynes CnH2n - 2

Cycloalkanes CnH2n

Cycloalkenes CnH2n - 2

Note: - alkene and cycloalkane compounds can be isomers of each other

- alkyne and cycloalkene compounds can be isomers of each other

Isomers are actually broken up into three main groups, namely;

1. Structural

2. Geometric

3. Stereo

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1. Structural Isomers

- Compounds that have the same molecular formula but different structures.

Hydrocarbon Isomer examples

C4H10

C5H10

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C6H14

C4H8

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2. Geometric Isomers

- Compounds that have the same molecular formula but different geometry

(physical arrangement)of bonds.

- Rotation in the double bond does not occur, so the groups of atoms

attached to the carbon in the double bond remain fixed, resulting in the

different geometries

- 2 Types of shapes:

- Cis - pronounced “sis,”

- groups on same side of double bond

- Trans - groups on opposite side of double bond

- Cis/Trans written as part of name

- e.g. cis-2-butene, trans-2-butene

Examples:

cis-2-butene trans-2-butene

cis-2-pentene trans-2-pentene

cis-2-hexene trans-2-hexene

cis-3,4-dimethyl-3-hexene trans-3,4-dimethyl-3-hexene

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Chemistry 2202

Organic Chemistry: Aliphatic Hydrocarbons_Isomers Name:__________________ (Aliphatic Hydrocarbons_Isomers_1)

Fill out the chart below with as many isomers of C6H12 as possible.

Structural Formula Name

33

Complete Structural Formula

Name

34

3. Alkynes

- basic formula CnH2n-2

- inert (non-reactive) in many chem rxns

- hydrocarbons with at least one triple bond

- alkynes are also referred to as un-saturated hydrocarbons because there are

multiple C-C bonds since each carbon does not have the maximum number of

hydrogens attached.

Examples

- Ethyne C2H2 - simplest alkyne

- common name is acetylene

- used in oxyacetylene torches for welding

- used as a fuel

- Pentyne C5H8

- natural rubber - sticky in hot weather and brittle in cold weather

- synthetic rubber - is produced in great quantities today through a

process called vulcanization (Vulcan - Roman God of the fire)

Naming Alkynes 1. Count longest chain of C atoms. Name using the appropriate prefix plus “yne.”

2. Locate triple bond and use number to indicate location on chain. Count from the end

that is closest to the triple bond.

]

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Examples

Structural Formula Name

36

Naming Branched Chain Alkynes - The method of naming is similar to the alkenes except you count from the end of the

carbon molecule that is closest to the triple bond, not the end closest to the branch.

Examples

Structural Formula Name

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Summary of Aliphatic Pure Hydrocarbons

Aliphatic

Hydrocarbon

Compound

Formula

Bond

Type

Example

Alkanes CnH2n +2 single C3H8

Cycloalkanes CnH2n single C3H6

Alkenes CnH2n double C3H6

Cycloalkenes CnH2n-2 double C3H4

Alkynes CnH2n-2 triple C3H4

Note that cyclo-alkanes and alkenes are isomers of each other, as are cyclo-alkenes and alkynes.

38

Chemistry 2202

Organic Chemistry: Aliphatic Hydrocarbons Name:__________________ (Aliphatic Hydrocarbons_1) Compound

Skeletal SF

Condenced SF

Line SF

octane

propyne

2,3-dimethylpentane

3-hexene

4-ethyl-4-methyl-2-heptyne

3-ethyl-2,2-

dimethylhexane

cyclohexane

cyclohexene

2-ethyl-1-

propylcyclopentene

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Chemistry 2202

Organic Chemistry: Aliphatic Hydrocarbons Name:__________________ (Aliphatic Hydrocarbons_8) 1. Name the Following:

1

2

3

4

5

6

7

8

2. Draw the following: Alkene/Alkyne

Skeletal SF

Condensed SF

Line SF

2-octene

3,3-dimethyl-4-

octene

3-heptyne

cyclopropene

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Chemistry 2202

Organic Chemistry: Aliphatic Hydrocarbons Name:__________________ (Aliphatic Hydrocarbons_9) 1. Name the Following:

1

2

3

4

5

6

7

8

2. Draw the following: Pure

Hydrocarbon

Skeletal SF

Condensed SF

Line SF

1-butene

cycloheptene

1-butyne

cyclopropane

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Oil Refining

- crude oil (unprocessed) is formed from marine life buried in ocean sediment millions of years

ago

- it consists of alkanes, and small amounts of S, O, N

- we use physical and chemical processes to treat crude oil and make many marketable

products

- refined products include gas, crayons, plastics, jet fuel, asphalt, kerosene, fiber, etc.

- 95% of all petroleum is used as fuel for vehicles and industry

- 5% is used for a variety of household and industrial products such as plastics, detergents,

rubber, drugs, etc.

Newfoundland and Labrador reserves - Hibernia field has 1,200,000,000 barrels of oil and 64,000,000,000 barrels of gas.

- Terra Nova field has 440,000,000 barrels of oil

- White Rose field has 232,000,000 barrels of oil

- Hebron-Ben Nevis field has 700,000,000 barrels of oil

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Fractional Distillation

- oldest and most common method of obtaining a variety of components from crude oil

- physical process whereby crude oil is separated into diff components (fractions)

using diff in b.p.

Process:

- crude oil is heated up to a T of 600oC – crude oil becomes a gas(vapour)

- vapour enters bottom of column where it rises, cools and condenses in collection

trays

- 30 - 40 % of distilled crude oil is produced as gas(C4H10) and this amount still does

not meet demand (~ 50 % gas needed)

- Come By Chance oil refinery processes about 100, 000 barrels of crude per day

Oil refineries use both Cracking and Reforming processes to obtain further useful products

from the fractional distillation process.

Cracking

- larger HCs are cracked/broken into smaller, more

useful pieces

- thermal cracking - heat

- catalytic cracking - catalyst

- Ex: C17H36(l) -> C9H20(l) + C8H16(l)

- propane is sometimes cracked, or broken down to

produce methane, ethene, propene and hydrogen,

depending on what the hydrocarbon market needs

43

Reforming

- smaller HCs combined to make larger, more useful

ones

- platinum used as a catalyst

- Ex: C5H12(l) + C5H12(l) -> C10H22(l) + H2(g)

- sometimes straight chain alkanes are reformed to

produce branched chain alkanes, or other,

depending on what the hydrocarbon market needs.

Use as Fuel

- the number one use of refined oil is as fuel

- the release of energy of HCs is the chemical reaction known as combustion

2 C8H18(l) + 25 O2(g) -> 16 O2(g) + 18 H2O(g) + energy

- internal combustion engines are not 100 % efficient resulting in unwanted by-

products such as carbon monoxide, nitrous oxide, unburned HC

- U.S. market consumes 500,000,000,000 barrels per year (131 t. gallons)

- 1 gallon is enough enegry to cook 110 McD hamburgers

- eq. to 1500 watt heater left on for 24 hours

more info: http://www.youtube.com/watch?v=jk0WrtA8_T8

44

Aromatics - historically named because of their odour/aroma

- current defined as a compound with at least one benzene ring structure

Common Compounds and Uses:

- artificial flavouring (ex: vanillin)

- ASA (aspirin)

- benzocaine (local anesthetic)

- adrenaline (natural)

- released by the body in response to anxiety, exercise or fear. It is a

natural stimulant that the body uses to control heart rate, sweat

secretion, saliva production, etc.

- amphetamines (synthetic) version of adrenaline

- acts as a stimulant creating greater alertness and a feeling of prowess.

- First used as a treatment for asthma, later used by military in WW2

and Vietnam as a stimulant.

- Today marketed as illicit drugs such as speed, methamphetamine and

ecstacy.

Adrenaline Amphetamines

- styrene (plastic starting material)

- added to gas to improve burn quality

45

Benzene Structure

- basic formula C6H6(l)

- the structure remained a mystery for long time because of its similar formula to a

cycloalkene

- testing, however, proved all the bonds in benzene were the same length and that its

behaviour was more like an alkane than an alkene.

- in 1865 August Kekule proposed a cyclic structure for the

compound benzene. He suggested that benzene has 6 C

atoms, each bonded to 1 H atom. He also suggested that the

remaining unpaired bonding electrons were delocalized.

- delocalized electrons results in a strong hybrid

(single/double) bond between C atoms

- these bonds make benzene stable

- drawn as hexagon with an circle inside. Benzene, however,

was traditionally written with a triple bond inside the ring

type structure.

Complete

Line

Benzene Properties

- liquid at room temperature

- boiling point 80.1oC

- planar

- non-polar (soluble in non-polar solvents)

Branched Benzene Structures (Alkyl Benzene)

- any of benzene’s six atoms can be substituted by an alkyl group. We consider only

two types of substitutions with benzene compounds, namely

- mono-substituted

- di-substituted

46

Mono-substituted Benzene

-refers to benzene structures with only one hydrogen atom substituted by an alkyl group.

Naming Mono-substituted benzene structures. - Use benzene as the parent name

- Determine name of the alkyl group

- Add alkyl group name as a prefix (no position needed)

Examples

Structural Formula Compound Name

47

Di-substituted Benzene

- refers to benzene structures with two hydrogen atoms substituted by two

alkyl groups.

- This results in three possible arrangements of the alkyl group around the

benzene structure, as follows in the diagram below

- As a result, this means there are three possible isomers of each compound.

1 and 2 1 and 3 1 and 4

Naming Di-Substituted Benzene Structures

- To name di-substituted benzene structures you simply count clockwise

from the first branch, or from the most complex branch, and the position

of the alkyl groups is identified using the following system of prefixes.

Prefix Position of alkyl groups

Ortho (O) 1 and 2

Meta (M) 1 and 3

Para (P) 1 and 4

48

Examples

Structural Formula Compound Name

49

Chemistry 2202 Organic Chemistry: Aromatics(Benzene Structures) Name:__________________ (Aromatics_1) Structural Formula

Compound Name

Name 1________________________

Name 2________________________

Name 1________________________

Name 2________________________

Name 1________________________

Name 2________________________

1-ethyl-3-phenylbenzene

o-propylbenzene

50

Phenyl Groups

- some carbon compounds have a benzene branch that is part of another

structure.

- In this case the benzene structure is referred to as a phenyl group.

Note: these structures will be named using the naming system for

branched chain alkanes.

Examples

Structural Formula Compound Name

51

Polymerization

Monomers - ‘mono’ - meaning ‘one’

- small carbon based molecular units.

Polymers - ‘poly’ - meaning ‘many’

- long carbon based compounds whose molecules are made

up of connected monomers. Polymers can be compared to

individual links in a chain.

- sometimes form very large(giant) molecules

- a polymer may contain one, or more, types of monomers

- can be formed naturally

- proteins (10 billion on Earth)

- examples include glucose and fructose

- can be formed synthetically

- plastics

- there are two methods of producing

synthetic polymers

- Addition polymerization

- Condensation polymerization

- good time to discuss the problems associated with synthetic

polymers and their long life as pollution in our

environment.

- long life of materials

- wildlife concerns

- litter concerns

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Addition Polymerization

- this type of reaction occurs when unsaturated monomers react to form

longer chain polymers

- monomers join in a process that involves breaking double and/or triple

bonds between carbon atoms in the monomer.

- some products include polyethylene materials such as plastic, wire

insulation, plastic freezer dishes, lab grade wash bottles, etc.

Examples

Condensation Polymerization

- formed by a head-to-tail joining of monomers that usually results in the

formation of a polymer and some small molecule such as H2O, NH3 and

HCl.

Eg. glucose + fructose → sucrose + water.

- some products of this type of reaction include nylon materials, polyesters,

tires, and many other household and industrial products.

Examples

See page 429-430 of text for example

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Chemical Reactions Involving Pure Hydrocarbons

We Will:

- Identify Reaction Type

- Draw Structural Formulas of organic reactants and products.

- Predict products.

- Determine name/structure of a missing compound in a reaction.

Reaction Types

1. Substitution

2. Addition

3. Cracking

4. Reforming

5. Complete Combustion

6. Incomplete Combustion

Halocarbon

- alkane or benzene with halogen attached

- not found in nature

- often used as an anesthetic

Chloroethane Trichloromethane Chlorobenzene

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1. Substitution

- Alkanes and Benzene structures undergo Substitution Reactions

- Reactions often occurs in the presence of light

- Light serves as a catalyst

- Reactions generally slow – strong covalent bonds difficult to break

- always involves two reactants and two products

General Equation:

R-H + X2 R-X + H-X

Where:

R - any alkane or benzene structure

X2 - any halogen

R-X - halocarbon(organic halide)

- alkane or benzene with halogen attached

H-X - hydrogen halide

- hydrogen with halogen attached

Subtype 1: Alkane Single Substitutions

- Example 1: Ethane reacts with chlorine

- Example 2: Propane reacts with bromine

- Example 3: Butane reacts with fluorine

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Subtype 2: Alkane Double Substitutions

(Note excess halogen reactant)

- Example 1: Ethane reacts with excess chlorine

- Example 2: Propane reacts with excess bromine

Subtype 3: Benzene Substitutions

- benzene behaves chemically like an Alkane

- like alkanes, it is very stable and almost unreactive

- a catalyst if often needed for benzene reactions Ex: iron

- Example 1: Benzene reacts with chlorine

- Example 2: Benzene reacts with fluorine

- Example 3: Benzene reacts with excess bromine

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Complete the following:

1. Benzene reacts with iodine

2. Pentane reacts with excess chlorine

3. Propane reacts with bromine

4. Butane reacts with excess fluorine

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2. Addition Reactions - Alkenes and Alkynes undergo addition reactions

- Alkenes and Alkynes are more chemically reactive

- In Alkene – double bond is broken into a single bond

- In Alkyne – triple bond is broken into a double bond or single bond

- Results in free bonding electrons around the site of the old multiple bond

- Always involved two reactants and one product

- Note: Hydrogen atom is not removed from Alkene/Alkyne

General Equation

-C=C- + X-Y X-C=C-Y

Where:

- -C=C- - alkene or alkyne

- X-Y - H2O, halogen or hydrogen halide

- X-C=C-Y - single product

Subtype 1: Halogen Addition

- halogen adds on to double/triple bond site

- Example 1: Ethene reacts with chlorine

- Example 2: Ethyne reacts with chlorine

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- Example 3: 1-butyne reacts with bromine

- Example 4: 1-butyne reacts with excess bromine

Note: all multiple bonds are broken

Subtype 2: Water Addition

- H and OH add on to double/triple bond site

- Example 1: 1-butene reacts with water

- Example 2: 1-butyne reacts with water

- Example 3: propene reacts with excess water

- Example 4: 2-butyne reacts with excess water

Note: all multiple bonds are broken

Subtype 3: Hydrogen Halide Addition

- H and halogen add on to double/triple bond site

- Example 1: 1-propene reacts with hydrogen bromide

- Example 2: cyclohexene reacts with hydrogen chloride

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Chemistry 2202

Organic Chemistry: Organic Reactions Name:__________________

Complete the following Addition Reactions.

1 1-butene reacts with chlorine

2 1-proene reacts with water

3 1-butyne reacts with water

4 1-propyne reacts with fluorine

5 Cyclohexene reacts with hydrogen bromide

6 1-propyne reacts with hydrogen iodide

7 2-pentyne reacts with excess chlorine

8 2-pentyne reacts with water

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9 1-propyne reacts with excess bromine

10 2-butene reacts with excess hydrogen chloride

11 cyclobutene reacts with water

12 ethyne reacts with excess bromine

13 3-heptene reacts with iodine

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Chemistry 2202

Organic Chemistry: Organic Reactions Name:__________________

Addition Reactions - alkenes and alkynes - one product only

Substitution Reactions - alkanes and benzene - two products

1. Complete the reaction and name the type for each of the following;

Organic Reaction Type

Cyclohexene + water

Benzene + bromine

Propane reacts with iodine

Ethene reacts with iodine

2. Complete the reaction and name the reaction type for each of the following

Organic Reaction Type

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Type 3: Cracking

- long hydrocarbons, in the presence of heat and/or a

catalyst, are broken down into shorter hydrocarbons

General Formula:

Long Chain Hydrocarbon + H2 Short Chain Hydrocarbon

- Example 1:

- Example 2:

Type 4 : Reforming - short hydrocarbons, in the presence of heat and/or a

catalyst are connected to form longer hydrocarbons

General Formula:

Short Chain Hydrocarbon Long Chain Hydrocarbon + H2

- Example 1:

- Example 2:

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Type 5: Complete Combustion

General Formula:

CxHy + O2 CO2 + H2O

- Example 1:

- Example 2:

Type 6: Incomplete Combustion

General Formula:

CxHy + O2 CO + C + CO2 + H2O

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Chemistry 2202

Organic Chemistry: Chemical Reactions Name:__________________

(Chemical Reactions_1)

There are Six types of Chemical Reactions:

1. Substitution R-H + X2 → R-X + HX

2. Addition C=C + X-Y → X-C-C-Y

3. Combustion CxHy + O2 → CO2 + H2O

4. Incomplete

Combustion CxHy + O2 → C + CO + CO2 + H2O

5. Cracking long HC chain + H2 → shorter HC chains

6. Reforming short HC chains → long HC chain + H2

1. Name each of the following reaction types.

A) + HOH → __________

B) C5H12 + C3H8 → C8H18 + H2 __________

C) -C-C-C- + I2 → -C-C-C-I + HI __________

D) CH4 + 2 O2 → CO2 + 2 H2O __________

E) + Br2 → + HBr __________

F) C17H36 + H2 → C9H20 + C8H18 __________

G) -C C-C- + 2 HCl → -C-C-C- __________

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2. Predict the products and name each of the following reaction types.

A) + I2 → __________

B) -C C- + 2 I2 → __________

C) -C-C-C-C=C- + HOH → __________

D) -C-C-C-C-C- + O2 → __________

E) + HBr → __________

3. Write the structural formula of the missing reactant and name the reaction type.

A) ______ + H-Cl → -C-C-H __________

B) ______ + Cl2 → + HCl __________

C) ______ + HOH → C=C __________

D) ______ + Br2 → + HBr __________

E) ______ + 2 HOH → -C-C-C-C- __________

F) ______ + Cl2 → __________

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4. Write balanced chemical equations for each of the following hydrocarbon combustion reactions.

A) ethane

B) butane

C) hexane

D) 2,2,3-trimethylpentane

E) benzene

F) cyclobutane

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5. Draw the structural formulas of reactants and products.

A) the cracking of heptane into propane and butane

B) the cracking of 2-methylpentane with hydrogen to produce two propanes

C) the cracking of 1-butene to produce ethyne and ethane

D) the cracking of a hydrocarbon and one hydrogen to produce methane and propane

E) hexane + ethane → octane + hydrogen

F) 2-methylbutane + propane → 3,3-dimethylhexane + hydrogen

G) the forming of decane and hydrogen from two pentanes

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Chemistry 2202

Organic Chemistry: Chemical Reactions Name:__________________

MATCH-UP the organic reaction with the reaction TYPE:

1. ____Addition A. -C-C-C- + F2 → -C-C-C-F + HF

2. ____Cracking B. CH4 + 2 O2 → CO2 + 2 H2O

3. ____Combustion C. C8H18 + C9H20 → C17H36 + H2

4. ____Reforming D. -C-C C- + 2 HBr → -C-C-C-

5. ____Substitution E. C20H42 + H2 → C10H22 + C10H22

PREDICT the following reactions:

6. + HOH →

7. + Cl2 →

8. -C-C-C-C-C- + 2 I2 →

9. -C-C C-C- + F →

WRITE STRUCTURAL formulas for the following reactions:

10. 2-methylpentane and hydrogen cracked to produce propane

11. hexane + ethane → 3-ethylhexane + hydrogen

BALANCE the following reaction:

___C8H18 + ___ O2 → ___CO2 + ___H2O

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Chemistry 2202

Pure Hydrocarbons Review (Pure Hydrocarbons Review)

Terms to Know

Organic Chemistry

Organic Compound

Inorganic Compound

Frederick Wohler

Pure Hydrocarbon vs. Hydrocarbon Derivative

Isomer - Structural, Geometric, Stereoisomer

Structural Formula - Complete, Condensed, Skeletal, Line

Functional Group

Homologous Series

Saturated vs. Unsaturated Hydrocarbon

Crude Oil

Fractional Distillation

Cracking/Reforming

Complete vs. Incomplete combustion

Aliphatic Hydrocarbon - Alkanes, Alkenes, Alkynes

Alkanes (CnH2n+2), Cycloalkanes (CnH2n)

Alkenes (CnH2n), Cycloalkenes (CnH2n-2)

Alkynes (CnH2n-2)

Aromatic - Benzene (C6H6)

August Kekule

Delocalized Electrons/Hybrid

Monosubstituted vs. Disubstituted Benzene

Phenyl Groups

Addition and Substitution

Concepts to Know

Properties of carbon

Naming and Drawing Alkane, Alkene, Alkyne and Benzene structures

Straight Chain, Branched Chain, Cyclic structures

Properties of Pure Hydrocarbons

Formulas, Boiling Points, Solubility, Reactivity

Examples of Pure Hydrocarbons

Predicting of Isomers

Oil Refining Process

Polymerization

Naming Reaction Type and Balancing Equation

Addition

Substitution

Cracking

Reforming

Complete Combustion

Incomplete Combustion

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