Ch 25 Hydrocarbon Compounds

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Transcript Ch 25 Hydrocarbon Compounds

Ch 25 Hydrocarbon Compounds
Carbon
• Make a list of everything you know of that
contains carbon:
Ch 25.1 Hydrocarbons
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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 CH4
CH4
Ethane
C2H6
CH3CH3
Propane
C3H8
CH3 CH2 CH3
Butane
C4H10
CH3 CH2 CH2 CH3
Pentane
C5H12
CH3 CH2 CH2 CH2 CH3
Hexane
C6H14
CH3 CH2 CH2 CH2 CH2 CH2 CH3
Heptane C7H16
CH3 CH2 CH2 CH2 CH2 CH2 CH2 CH3
Octane
C8H18
CH3 CH2 CH2 CH2 CH2 CH2 CH2 CH2
CH3
Nonane
C9H20
CH3 CH2 CH2 CH2 CH2 CH2 CH2 CH2
CH2 CH3
Decane
C10H22
CH3 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
Natural Gas
Petroleum
Ether
Naptha
Gasoline
Kerosene
Fuels Oils
Grease, Tar
Carbon
Chains
1-4
5-6
Boiling
Range (0C)
Below 20
30-60
7-8
6-12
12-15
15-18
16-24
60-90
40-175
150-275
225-400
Over 400
Percent Crude
Oil
10
40
10
30
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
• 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 1,2ethanediol. 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
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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
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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
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(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),
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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: