Ch 25 Hydrocarbon Compounds

Carbon

• Make a list of everything you know of that contains carbon:

Ch 25.1 Hydrocarbons

• Organic Chemistry

• Straight Chain Alkanes

• Branched Chain Alkanes

• Properties of Alkanes

Organic Chemistry

• Chemistry of all carbon compounds

• Over 1 million compounds

• Hydrocarbons – organic compounds with only carbon and hydrogen

• Alkanes – simplest hydrocarbons

Methane

Methane

• CH4

• Carbon always forms 4 covalent bonds

Straight Chain Alkanes

• A number of carbon atoms, one after another

• Ethane

Reference Table

• Table Q – Types of Hydrocarbons

• Table P - Prefixes

Name Molecular Formula

Structural Formula

Methane CH4CH4

Ethane C2H6CH3CH3

Propane C3H8CH3 CH2 CH3

Butane C4H10CH3 CH2 CH2 CH3

Pentane C5H12CH3 CH2 CH2 CH2 CH3

Hexane C6H14CH3 CH2 CH2 CH2 CH2 CH2 CH3

Heptane C7H16CH3 CH2 CH2 CH2 CH2 CH2 CH2 CH3

Octane C8H18CH3 CH2 CH2 CH2 CH2 CH2 CH2 CH2

CH3

Nonane C9H20CH3 CH2 CH2 CH2 CH2 CH2 CH2 CH2

CH2 CH3

Decane C10H22CH3 CH2 CH2 CH2 CH2 CH2 CH2 CH2

CH2 CH3

Branched Alkanes

• Substituent – atom or group of atoms that takes the place of as hydrogen atom

• An alkane with one or more branched groups

Ch 25.2 Unsaturated Hydrocarbons

• Alkenes

• Alkynes

Alkenes

• Hydrocarbons containing carbon to carbon double bonds

Saturated vs. Unsaturated

• Saturated – organic compound in which all carbon atoms are joined by single covalent bonds, contains the maximum number of hydrogen compounds

• Unsaturated – organic compound with one or more double or triple carbon-carbon bonds

Alkynes

• Hydrocarbon containing carbon to carbon triple bonds

Ch 25.3 Isomerism

• Isomer – same molecular formula, different structural formula

Chapter 25.4 Hydrocarbon Rings

• Cyclic Hydrocarbons

• Aromatic Hydrocarbons

Cyclic Hydrocarbons

• Compounds where the end carbon of the chain are attached to each other forming a ring

• Aliphatic Compounds – hydrocarbon that are chains, not rings

Aromatic Hydrocarbons

• Arenes – unsaturated cyclic hydrocarbons, contain single rings or groups of rings

• Aromatic Compound – any substance in which the bonding is like benzene

Benzene

• C6H6

Chapter 25.5 Hydrocarbons from Earth

• Natural Gas

• Petroleum

• Coal

Fraction Carbon Chains

Boiling Range (0C)

Percent Crude Oil

Natural Gas 1-4 Below 20

10Petroleum Ether

5-6 30-60

Naptha 7-8 60-90

Gasoline 6-12 40-175 40

Kerosene 12-15 150-275 10

Fuels Oils 15-18 225-400 30

Grease, Tar 16-24 Over 400 10

• The graph below shows the relationship between boiling point and molar mass at standard pressure for pentane, hexane, heptane, and nonane.

• Octane has a molar mass of 114 grams per mole. According to this graph, what is the boiling point of octane at standard pressure?

• State the relationship between molar mass and the strength of intermolecular forces for the selected alkanes.

•Allow 1 credit for 124°C 2°C.•Allow 1 credit. Acceptable

responses include, but are not limited to:– As molar mass increases, there are

stronger intermolecular forces.– The forces are greater between

heavier molecules.

• The compound 1,2-ethanediol can be mixed with water. This mixture is added to automobile radiators as an engine coolant. The cooling system of a small van contains 6690 grams of 1,2-ethanediol. Some properties of water and 1,2-ethanediol are given in the table below.

• Identify the class of organic compounds to which 1,2-ethanediol belongs.

• State, in terms of molecular polarity, why 1,2-ethanediol is soluble in water.

• In the space in your answer booklet, calculate the total number of moles of 1, 2-ethanediol in the small van’s cooling system. Your response must include both a correct numerical setup and the calculated result.

• Allow 1 credit. Acceptable responses include, but are not limited to: alcohol

• Acceptable responses include, but are not limited to:– Water and 1,2-ethanediol molecules are both

polar.– Both molecules have similar polarity.

• • Allow 1 credit for a correct numerical setup. Acceptable responses include, but are not limited to:

• • Allow 1 credit for 108 mol or for a response consistent with the student’s numerical setup.

• A gasoline engine burns gasoline in the presence of excess oxygen to form carbon dioxide and water. The main components of gasoline are isomers of octane. A structural formula of octane is shown below.

• One isomer of octane is 2,2,4-trimethylpentane.• In the space in your answer booklet, draw a

structural formula for 2,2,4-trimethylpentane. [1]• Explain, in terms of the arrangement of particles,

why the entropy of gasoline vapor is greater than the entropy of liquid gasoline.

• The arrangement of molecules in the vapor state are more random or disordered.

• Particles in the vapor state are farther apart and move more freely.

Chapter 26 Functional Groups

• Halide (Halocarbons)

• Alcohols

• Ethers

• Aldehydes

• Ketones

• Carboxylic Acids

• Esters

Halide (Halocarbons)

• Organic compounds covalently bonded with fluorine, chlorine, bromine, or iodine

• Naming: number – halide prefix – name

– 1- Chlorohexane

• R – X (X = any halogen)

Alcohols

• Organic compounds with an –OH group

• - OH group = Hydroxyl group

• Naming: number – name – ol ending– 2 - butanol

Primary, Secondary, Tertiary Alcohols

• Primary Alcohol – only 1 carbon attached to the primary C – OH

• R – CH2 – OH

• Secondary Alcohol – 2 carbons attached to the primary C – OH

• R – CH – OH R

• Tertiary Alcohol – 3 carbons attached to the primary C – OH

R• R – C – OH R

Ethers

• Organic compound in which oxygen is bonded to two carbon groups

• R – O –R• Naming: name each group on each side of

the oxygen, then use alphabetical order and ends with ether– CH3CH2OCH3

– Ethyl methyl ether

Aldehydes

• Organic compound in which the carbon of the carbonyl group is bonded with at least one hydrogen

• R-CH-O• Naming: name the longest chain, drop the e

ending, add al• H – C = O H• Methanal

Ketones

• Organic compound in which the carbon of the carbonyl group is bonded to two other carbons

• R – C =O

R

• Naming: Naming: name the longest chain, drop the e ending, add one

Carboxylic Acids

• Organic compound with a carboxyl group

• R – C =O

OH

• Naming: Drop the e add oic acid

• RCOOH

Esters

• Carboxylic acid with the OH replaced by an OR

• R – C = O

O – R

• Naming: drop the e, add oate

Dehydration Synthesis

• The linking of two organic compounds by removing water from functional groups.

Etherification

• a) requires 2 alcohols

• b) H2SO4 is the dehydrating agent. It removes H from one alcohol molecule and OH from the other to form H2O.

Esterification

• a) requires an alcohol and a carboxylic acid

• b) forms an ester, named for the alcohol and acid that formed it.

Fermentation

• Fermentation of glucose or fructose in corn, barley, grapes, apples, etc. forms ethanol:

• The reaction proceeds until the alcohol content reaches 13%, at which point the yeast dies. Further increases in concentration may be yielded by distillation. Used in alcoholic beverages where, in the synthesis of acetic acid (by catalytic oxidation) and it is used as a solvent.

Saponification• The production of soap.• a) Requires a glycerol ester (fat) and sodium

hydroxide (strong base)• b) The glycerol ester is dissolved in ethanol, and the

NaOH is mixed in.• c) The mixture is heated slowly until it thickens.• d) The alcohol solvent is now evaporated off.• e) The resultant mixture is glycerol plus the sodium

salts of the long-chain acids. The salts represents the soap.

• f) The salts may be precipitated out of the glycerol by adding NaCl and filtering out the glycerol. The resulting lump is soap.

Polymerization

POLYMER - an extremely large molecule made by connecting many smaller molecules together. The basic molecules used as "building blocks" of the polymer are called monomers.

• Monomer molecule = A• polymerization• 18 A -> A-A-A-A-A-A-A-A-A-A-A-A-A-A-A-A-A-A• Can be abbreviated as 18 A -(-A-)-18, which

represents a chain of A monomers 18 units long.

Types of Polymers:

• 1) Addition Polymers - formed by addition polymerization reaction: the monomer’s double bond opens, allowing

• the monomer units to join end to end. The name of the polymer is found by putting a “poly” in front of the monomer’s

• name. For example, propylene monomer forms polypropylene.

Polyvinyl Chloride

• 1. Formed from Vinyl Chloride monomer (chloro ethane)

• 2. The double bond breaks, and VC monomer units join end to end.

• 3. Used for water pipes, record albums, raincoats, shower curtains, wire insulation, vinyl siding

Polystyrene

• 1. Formed from styrene monomer (phenyl ethane, basically ethene with a benzene attached to it)

• 2. The double bond breaks, and styrene monomer units join together.

• 3. Used for plastic model kits, styrofoam

Polytetrafluoroethene (teflon)

• 1. Formed from tetraflouro ethene monomer

• 2. The double bond breaks, and TFE monomer units join together.

• 3. Used for no-stick pans.

• 4. Accidentally discovered in 1938 by Roy Plunkett.

Types of Polymers:

• 2) Condensation Polymers - formed by dehydration synthesis of difunctional monomer units. H and OH are removed

• from the ends of the monomer units, allowing them to join together. Water is given off as a byproduct.

Polyester

• 1. Formed from monomer units that have an alcohol functional group on one end and a carboxylic acid functional

• group on the other end.

• 2. The opposing ends undergo dehydration synthesis, and form the polymer.

Types of Polymers:• 3) Rubber• a) cis- Polyisoprene (tires), polybutadiene (tires),

polychloropropene (Neoprene...wire covering, automotive drive belts,

• wetsuit material)), Nitrile (automotive hoses and gaskets)• 1. Formed by addition polymerization• 2. The resultant macromolecule is tacky and not very strong. It

generally has a low melting point.• 3. In order to make this stuff serviceable, it must by toughened

up. This is done by a process whereby the polymer chains are cross-linked with sulfur. This toughens up the rubber. This process was discovered accidentally by Charles Goodyear in 1839. This process is called vulcanization.

• Unfortunately, when heat is applied to rubber so treated, it does not melt, but burns, releasing CO, CO2 and SO2.

Recognize a reaction

Determine reactants to make the desires product: