Organic Compounds

advertisement
Organic Compounds
Chapter 24
Organic Compounds




Section 1- Simple Organic Compounds slides
3-20
Section 2- Other Organic Compounds slides
21-32
Section 3- Petroleum- A Source of Carbon
Compounds slides 33-44
Section 4- Biological Compounds slides 45-62
Section 1 Simple Organic
Compounds




What You’ll Learn:
About organic and inorganic carbon
compounds
Difference between saturated and unsaturated
hydrocarbons
Identify isomers
1 Simple Organic Compounds



Most compounds that contain the element
carbon are organic compounds made by living
organisms or synthesized in laboratories.
More than 90 % of carbon compounds are
organic.
Others like carbon dioxide and carbonates are
inorganic compounds.
Why does carbon form so many
organic compounds?



With 4 electrons in its outer energy level,
carbon can form one covalent bond with each
of these electrons.
There are many C compounds because C can
form so many bonds.
Some are small like the ones used as fuel while
some are complex like those in medicine and
plastics.
How can C atoms arrange
themselves?

C atoms can bond
together as chains,
branched chains, &
rings.
How can C atoms arrange
themselves?




The first structure shows carbon bonded in a
straight chain as heptane, an organic
compound in gasoline.
The second structure, a branched chain, shows
isoprene, an organic compound in natural
rubber.
The third structure, a cyclic ring or chain, is
vanillin from vanilla flavoring.
Also forms single, double or triple covalent
bonds.
Hydrocarbons


A compound that is made of only carbon and
hydrogen is called a hydrocarbon.
Natural gas contains the hydrocarbon methane or
CH4.
Single Bonds

Hydrocarbons with only single-bonded C atoms are
called saturated hydrocarbons. It is saturated
because each C is bonded to as many H as possible.
Boiling Points of Hydrocarbons
butane
pentane
propane
ethane
methane
Boiling Points of Hydrocarbons


Did you see a pattern?
The boiling points of
saturated hydrocarbons
increase as the number
of carbon atoms in the
chain increases.
•Image
•File history
•Links
Can different hydrocarbons have the
same formula?

Butane is C4H10 and so is isobutane. Butane is a
straight chain molecule but isobutane has a branched
chain.
What are isomers?



Isomers are compounds that have the same
chemical formula, but have different molecular
structures & shapes.
Thousands of hydrocarbons are isomers.
Butane & isobutane are two of them.
Properties of Butane Isomers
Property
Butane
Isobutane
Description
Colorless gas
Colorless gas
Density
0.60 kg/L
0.603 kg/L
Melting Point
-135°C
-145°C
Boiling Point
-0.5°C
-10.2°C
Are there other kinds of isomers?

Some isomers differ only slightly in the way their
atoms are arranged. Some form what are called righthanded & left-handed molecules. These have nearly
identical physical and chemical properties.
Multiple Bonds



Ethene or ethlylene gas
is what makes fruit
ripen.
You can see ethene has
one double bond.
The two C atoms share
two pairs of electrons.
Multiple Bonds

The ethyne molecule has a
triple bond with two
carbon atoms sharing
three pairs of electrons.
Also called acetylene, it’s
used in welding torches.
Ethene and ethyne are
unsaturated hydrocarbons.
Multiple Bonds


An unsaturated hydrocarbon is one that has at
least one double bond or triple bond. The
compounds are unsaturated because each
carbon atom is not bonded to as many
hydrogens as possible.
The last three letters tell what type of bond is
in the molecule. Compounds ending in –ane
have only single bonds. Those with –ene have
at least one double bond and –yne signifies at
least one triple bond.
Flow Chart
Organic compounds
Contain only C & H are called
Straight chains
________ chains
_________ chains
Bond as
Single
bonds
_____
bonds
______
bonds
Flow Chart
Organic compounds
Contain only C & H are called
Straight chains
Branched chains
hydrocarbons
Cyclic chains
Bond as
Single
bonds
Double
bonds
Triple
bonds
Section 2 Other Organic Compounds




What You’ll Learn:
What aromatic compounds are
What alcohols and acids are
Some organic compounds you use everyday
2 Other Organic Compounds


Organic compounds
produce tastes and
smells such as
wintergreen, cloves,
cinnamon, and vanilla.
This is wintergreen or
methyl salicylate used
in chewing gum.
Aromatic Compounds



Other organic compounds
have unpleasant tastes or
smells.
This figure shows the
structural formula for
acetyl salicylic acid or
aspirin which has a sour
taste.
An aromatic compound
contains a benzene
structure having a ring
made of six C atoms.
Why is benzene stable?


The chemical structure
for benzene is C6H6.
The benzene ring is
made of six C atoms
bonded together by
three double bonds &
three single bonds
alternating around the
ring.
Why is benzene stable?



All 6 C equally share
the electrons making the
molecule very stable.
The symbol for benzene
is a circle inside a
hexagon.
Many organic structures
contain a benzene ring.
Are there other ring structures?



Organic compounds can
contain more than one
ring structure.
Some moth crystals are
made of naphthalene
with two rings fused
together.
Many contain 3 or more
rings fused together.
Substituted Hydrocarbons

Chemists change hydrocarbons into other
compounds with different physical & chemical
properties.


May add a double or triple bond
May substitute different atoms or groups of atoms
Substituted Hydrocarbons


A substituted hydrocarbon is a hydrocarbon
that has one or more of its hydrogen atoms
replaced by atoms or groups of atoms of other
elements.
Chemists decide what kinds of properties they
want in a new compound and then they choose
atoms or groups of atoms or types of bonds
that will give those properties.
What are some substituted
hydrocarbons?


An alcohol forms when
a hydroxyl group, –OH,
replaces one or more
hydrogen atoms in a
hydrocarbon.
This is ethanol. When
the sugars in grains or
fruits ferments, it
produces ethanol
What are some substituted
hydrocarbons?


Organic acids form
when a carboxyl group,
-COOH, attaches to a C
atom of a hydrocarbon.
Acetic acid is an organic
acid found in vinegar.
Other organic acids
include citric acid in
citrus fruit & lactic acid
in sour milk.
What other elements can be added to
hydrocarbons?


Chlorine can be used as
well as H & O.
When 4 Cl atoms
replace 4 H on ethene,
they form tetrachloroethene, a solvent
used in dry cleaning.
What other elements can be added to
hydrocarbons?




When 4 Fl atoms replace 4 H atoms, they form
a compound that can be made into a black,
shiny material used for nonstick cookware.
N, Br and S are also used in substituted
hydrocarbons.
Compounds called thiols are formed when S
replaces the O in the –OH group of an alcohol.
Thiols are also called mercaptans which smell
very bad such as skunk spray.
Section 3 Petroleum- A Source of
Carbon Compounds




What You’ll Learn:
How carbon compounds are obtained from
petroleum
How carbon compounds form long chains of
molecules
What polymers are
What is Petroleum?



Plastic comes from petroleum, a dark,
flammable liquid often called crude oil. It
exists deep within Earth. Coal, natural gas, &
petroleum are all called fossil fuels because
they come from fossilized material.
Oil wells pump crude oil to Earth’s surface.
Engineers separate the mixture by fractional
distillation at refineries in metal towers called
fractionating towers.
What is a fractionating tower?



As tall as 35 m, metal
plates are arranged to let
vapors pass through.
Pipes are attached at
different levels to
separate crude oil into
fractions using
distillation.
Depending upon their
boiling point, vapors
condense at particular
levels or temps.
What is a fractionating tower?


Crude oil is heated to
more than 350°C. Most
of the hydrocarbons turn
into vapor & begin to
rise inside the tower.
Vapors of the fractions
with the highest boiling
points only reach the
lowest plates before
condensing, draining off
& being collected.
Uses for Petroleum Compounds




Some fractions are used for fuels. Butane &
propane are some of the lightest fractions taken
from the top of the tower. Molecules of propane
have 3 C atoms; butane has 4 C atoms.
Molecules with 5-10 C atoms/molecule condense
on the upper plate & are used for gasoline &
solvents.
Those that condense on lower plates have 12-18
C atoms like kerosene & jet fuel.
Bottom fractions are lubricating oil with leftovers
used to make asphalt to pave roads.
Polymers



A polymer is a very large molecule made from
small molecules linked together like a chain.
A monomer is the small molecule that forms a
link in the polymer chain.
A polymer chain can contain as many as
10,000 monomers.
What are some common polymers?



Plastic is a common polymer made from the
monomer ethene or ethylene combined
repeatedly to make polyethylene for shopping
bags and plastic bottles.
Polypropylene is used to make glues and
carpets.
Copolymers consist of two or more different
monomers combined to make one polymer
molecule.
What are some common polymers?




Characteristics include being light & flexible.
So strong used to make plastic pipes, boats, car
bodies;
Used in place of wood & metal in buildings.
Some people call this the age of plastics.
What determines the properties of
polymer materials?


Their properties depend on which monomers are
used to make them– are they branched & what
shape are they?
Sometimes the same polymer can take two
completely different forms like polystyrene


Clear CD cases are by blowing CO2 into melted
polystyrene as it is molded
Foam cups & packing materials have bubbles
remaining in the polymer making it a good insulator.
What determines the properties of
polymer materials?

Polymers can be spun into thread & made into
tough fabrics for suitcases & backpacks or for
bulletproof vests.

Polymer fibers can stretch and return to their
original shape for exercise clothing.
What are some other petroleum
products?

Other products are made by separating
individual compounds from the petroleum
fractions & then changed into substituted
hydrocarbons to make:





Aspirin
Insecticides
Printing ink
Flavorings
Dyes
Are there some problems with
polymers?



Disposing of things made with polymers is a
problem because they do not decompose.
Recycling reuses clean plastics to make new
products.
Depolymerization uses heat or chemicals to
break long polymer chains into monomer
fragments which then can be used to make
other polymers. Too expensive to be practical
now due to different process for each polymer.
Section 4 Biological Compounds




What You’ll Learn:
About proteins, nucleic acids, carbohydrates,
and lipids
Polymers in food
Biological polymers
Biological Polymers

Many important biological compounds in your
body are biological polymers:



Huge molecules made of monomers
Larger than monomers of other polymers
Examples include proteins, nucleic acids,
carbohydrates, & lipids.
Proteins



Proteins are large
organic polymers formed
from organic monomers
called amino acids.
Only 20 amino acids can
make millions of
different proteins for
various tissues of your
body like muscles,
tendons, hair, fingernails,
etc.
Cell parts are pictured.
What are amino acids?



Amino acids are the
monomers that combine
to form proteins.
The figure shows the
structures of the amino
acids.
Each amino acid has an
amine group, -NH2 & a
carboxyl group,
-COOH.
What are amino acids?



The amine group of one
amino acid can combine
with the carboxyl group
of another amino acid.
This compound is a
peptide with a peptide
bond joining them.
A molecule containing
50 or more amino acids
is called a protein.
What do proteins look like?


Because proteins are
such a long chain, it
twists around itself &
can be identified by the
way it twists.
Many foods contain
proteins which your
body breaks into
monomers to make new
proteins for blood &
muscles, etc.
Nucleic Acids



Nucleic acids are another
group of organic polymers
that are essential for life.
They control cell activities
& reproduction.
DNA or deoxyribonucleic
acid codes & stores genetic
information (genetic code)
in the nuclei of cells.
What is DNA made of?



Monomers called
nucleotides make up
DNA.
Nucleotides contain an
organic base, a sugar, a
phosphoric acid unit.
Two chains of nucleotides
twist around each other
like a “twisted ladder” or
a double helix (spiral).
What is DNA made of?



Human DNA has 4 base
pairs which forms
millions of combinations.
The figure shows how
bases on one side of the
ladder link with the other
side to form a base pair.
The genetic code of DNA
gives instructions for
making other nucleotides
& proteins needed by the
body.
What is DNA fingerprinting?




Each molecule of DNA in your body has more
than 5 million base pairs.
Your DNA is unique unless you have an
identical twin.
DNA can be used to solve crimes by removing
the DNA from hair, blood, or saliva left at a
crime scene.
By breaking the polymer into monomers &
comparing the pattern to a suspect’s DNA,
they can link the suspect to the crime scene.
Carbohydrates



Carbohydrates are
organic compounds
made of C, H & O with
twice as many H atoms
as O atoms.
Carbohydrates include
sugars & starches.
Foods like bread &
pasta contain
carbohydrates.
What are sugars?

Sucrose C12H22O11



Sucrose is table sugar
which the body breaks
down into fructose &
glucose or more simple
sugars.
Fruit contains fructose.
Glucose is found in your
blood & in fruit & honey.
Eating sugar-rich food
gives you a quick boost of
energy.
Glucose C6H12O6
What is a starch?



Starch is a polymer
carbohydrate made of
monomers of glucose.
Your body breaks it into
sugars which release
energy into your cells.
Athletes use starches for
long lasting energy stored
in the liver & muscle cells
as glycogen for a fresh
burst of power.
Lipids



Lipids are organic
compounds like fats and
oils such as butter and
corn oil.
Lipids are made of C, H
& O but with fewer O
atoms than carbohydrates.
Another difference is that
lipids contain carboxyl
groups, -COOH while
carbohydrates do not.
What are some lipids in your diet?




Fats & oils are similar in structure to
hydrocarbons.
If they only have single bonds between C
atoms, they are saturated fats.
Unsaturated fat that has only one double bond
is monounsaturated.
An unsaturated fat that has two or more double
bonds is polyunsaturated
What are some lipids in your diet?




Fats are lipids that come
from animals.
Usually saturated &
solid at room
temperature.
Oils are unsaturated &
usually liquid at room
temperature.
Sometimes H is added
to vegetable oil to
saturate the C & make it
solid.
Cholesterol



Found in meats, eggs,
butter, cheese, & fish,
your body also produces
cholesterol & uses it to
build cell membranes.
Found in the digestive
fluid bile.
Can cause damage to
the heart & blood
vessels.
Cholesterol



Eating too many foods with high amounts of
saturated fats & cholesterol may cause heart
disease.
Some unsaturated fats may protect the heart
from disease.
A balanced diet contains some fats as well as
proteins & carbohydrates.
Download