sodium stearate
thymine
stearic acid
acryllic
uracil
cellulose
polypropylene
citric acid
chlorophyll
nylon
kevlar
acetic acid
pyruvic acid
insulin
hemoglobin
bakalite
ethyl alcohol
propane
isopropyl alcohol
methane
butane
freon
ether
urea
collagen keratin
elastin
testosterone
estrogen
formaldehyde
octane
ascorbic acid
paraffin
cytosine
guanine
starch
polyethlyene
PVC
adenine
acetone
folic acid
sucrose
lactose
glucose
aspartame
MSG
aspirin
pepsin
lactase
salivary amylase
naproxen
reverse transcriptase
acetaminophen
sodium stearate
thymine
stearic acid
acryllic
uracil
cellulose
polypropylene
citric acid
chlorophyll
nylon
kevlar
aceitc acid
pyruvic acid
insulin
hemoglobin
bakalite
ethyl alcohol
propane
isopropyl alcohol
methane
butane
freon
ether
urea
collagen keratin
elastin
testosterone
estrogen
formaldehyde
octane
ascorbic acid
paraffin
cytosine
guanine
starch
polyethlyene
PVC
adenine
acetone
folic acid
sucrose
lactose
glucose
aspartame
MSG
aspirin
pepsin
lactase
salivary amylase
naproxen
reverse transcriptase
acetaminophen
Init: 6/2/2010 by Daniel R. Barnes
WARNING: Various graphical elements in this presentation may have been taken from the world wide web without the permission of
their copyright owners. Do not copy or distribute this presentation. Its very existence may be illegal.
WARNING: The teacher who made this presentation frequently uses Wikipedia as an information source. Proceed with caution.
Life as we know it is “carbon-based”.
The more you study biology,
the more you begin to get the suspicion that
Okay, so that might be overstating the case a bit, but life
processes sure are full of chemical reactions.
Biological structures are made of molecules, too, so organic
chemistry is the basis of both the structure and function of life.
What kinds of molecules make life possible?
(part of fat = fuel/insulation)
DNA
stearic acid
(genes)
glucose
hexokinase
(an enzyme)
(sugar = fuel &
building materials)
http://www.youtube.com/watch?v=nqDHwd9rG0s
http://www.youtube.com/watch?v=7siZ0ON0b8I&feature=fvst
6
C
Carbon
12.01
“Organic chemistry” these days means “the chemistry
of carbon compounds”, but the word “organic” does not
literally mean “having carbon”. “Organic” means
“coming from or having to do with living things”.
At first, chemists thought that only living things could
make carbon compounds.
It is true that the bodies of living things carry out many
complex chemical reactions that produce lots of fancy
carbon compounds.
However, one day, some guy made a chemical in his
laboratory from totally nonliving materials . . .
Ammonium cyanate decomposes to ammonia and cyanic
acid which in turn react to form urea in a nucleophilic
addition followed by tautomeric isomerization:
Friedrich Wöhler
(31 July 1800 –
23 September 1882)
The Wohler synthesis of urea.
1828
Thanks to this guy, the word “organic chemical” no longer means
“chemical produced naturally by the body of a living thing”.
Friedrich Wöhler
(31 July 1800 –
23 September 1882)
The Wohler synthesis of urea.
1828
That’s all nice, but why are we
studying organic chemistry?
SWBAT
. . . relate organic chemical diversity to
carbon’s bonding habits.
6
Why carbon?
Why should carbon be the basis
of the chemistry of life?
C
Carbon
12.01
“valence electrons”
C
H
H C H
H
H
H C H
H
H
methane
H C H
H
H
is from group
1A
so it has
1 dot
so it forms
1 bond
O
is from group
6A
so it has
6 dots
so it forms
2 bonds
N
is from group
5A
so it has
5 dots
so it forms
3 bonds
C
is from group
4A
so it has
4 dots
so it forms
4 bonds
H
Br
P
N
FI C H
Cl
O
H
C
S
H
H
Br
P
N
FI C H
Cl
O
H
C
S
C
H
Br
P
N
FI C H
Cl
O
H
C
S
N
H
H. . .
Br
P
N
FI Cet cetera
Cl
O
H
C
S
O
H
1
10
= 10 possibilities
O 102 = 100 possibilities
1 bond
2 bonds
N
3
10
= 1000 possibilities
C
4
10
= 10,000 possibilities 4 bonds
3 bonds
*This table is based on VERY ROUGH approximations of compound diversity potential
Of course, carbon compounds
aren’t limited to having only
one carbon atom in them . . .
Carbon atoms can form structures ranging
from the small to the large,
and from the simple to the complex.
There seems to be no limit to the length of the carbon
“backbone”
This is a molecule of “icosane”, C20H42.
It’s not the longest possible hydrocarbon.
In fact this is the shortest of the hydrocarbons used to make
petroleum-based candle wax.
H H
H H
H H
H H
H H
H H
H H
H H
H H
H H
C
C
C
C
C
C
C
C
C
C
H
C
C
C
C
C
C
C
C
C
C
H
H H
H H
H H
H H
H H
H H
H H
H H
H H
H H
It’s long enough, though, that the chemist who made this picture
made an “skeletal formula” to represent the molecule.
In a skeletal formula, there is an “implicit” carbon atom at the end
of every line, unless another letter is already written there.
Also, each carbon will have as many unwritten hydrogen atoms
bonded to it as it can hold onto with its remaining “free hands”.
This is a molecule of “icosane”, C20H42.
It’s not the longest possible hydrocarbon.
In fact this is the shortest of the hydrocarbons used to make
petroleum-based candle wax.
It’s long enough, though, that the chemist who made this picture
made an “skeletal formula” to represent the molecule.
In a skeletal formula, there is an “implicit” carbon atom at the end
of every line, unless another letter is already written there.
Also, each carbon will have as many unwritten hydrogen atoms
bonded to it as it can hold onto with its remaining “free hands”.
Since a nitrogen atom can form three covalent bonds, it is
possible to form a chain out of nitrogen atoms.
Cl
H
H
H
F
N
N
H
N
N
H
Br
N
N
N
N
H
H
O
H
H
Si
H
If a nitrogen atom is holding onto its two next-door neighbors
with two of its bonds, it even has one bond left to hold onto a
third atom, increasing the potential for molecular diversity.
It turns out, though, that nitrogen chains are highly explosive.
They’re just not stable enough to be the basis of molecules in
a living thing.
It seems that nitrogen atoms would much rather form little N2
molecules than form large molecules.
N N N N N N N N N N
Living things that explode tend
to become dead things.
Sorry, nitrogen.
You don’t get the job.
Carbon, you’re hired.
You can’t form stable
chains.
Your chains and polymers are
stable at earthly temperatures.
You only make three
bonds.
You can make FOUR bonds.
Life on Earth will be based on
you. Congratulations.
Hydrocarbon molecules can also have branching structures.
normal octane (no branching)
isooctane
Hydrocarbon molecules can also have branching structures.
That name is too complicated.
Can we just call it “Trixie” instead?
Carbon can also form rings.
Benzene
Carbon can make multi-ringed structures, too.
Cholesterol
Carbon can make multi-ringed structures, too.
Testosterone
Carbon can make multi-ringed structures, too.
caffeine
Carbon can make multi-ringed structures, too.
serotonin
Carbon can make multi-ringed structures, too.
LSD
Carbon can also form bizarre molecules called “fullerenes”.
This particular one, whose formula is C60, is called a
“buckyball”.
Boy, carbon sure can make some wacky structures thanks to
its quadruple bonding capabilities! Zowie!
But there’s more . . .
Please note carbon’s position
on the periodic table.
Carbon is in group 4A 
A carbon atom has 4 valence electrons 
Carbon needs 4 more valence
electrons to have an “octet” of 8 
A carbon atom likes to make 4
covalent bonds.
C
A carbon atom can make 4
single bonds, or it can make a
combination of single, double,
and triple bonds, as long as the
total number of bonds is 4.
Double vs. single bonding
results in yet another source of
organic chemical diversity . . .
. . . the issue of . . .
C
C
C C
How many dots
does each carbon
atom have now?
H
How is a carbon
atom most likely
to get those
needed valence
electrons?
H H
How many dots
does each carbon
want to have?
CC
H
H H
How many more
dots does each
carbon atom
need?
Let’s make some
covalent bonds so
our carbons can
get their octets and
be happy.
H
H H
CC
H H
H
Let’s make some
covalent bonds so
our carbons can
get their octets and
be happy.
HH
H CC H
HH
Let’s make some
covalent bonds so
our carbons can
get their octets and
be happy.
This is the Lewis
structure for
ethane, C2H6.
HH
HCCH
HH
Covalently
bonding with four
other atoms gave
each carbon atom
a nice, full octet.
How many valence
electrons does
each carbon atom
have now?
HH
HCCH
HH
This molecule is said to be “saturated” because it contains
the maximum possible amount of hydrogen.
It is also possible for hydrocarbons to be “unsaturated”.
Such molecules have less hydrogen than they could.
HCCH
HH
This molecule is said to be “unsaturated” because it contains
less than the maximum possible amount of hydrogen.
When the two hydrogen atoms left, they took their electrons
with them, so now the C’s don’t have octets anymore.
HCCH
HH
This molecule is said to be “unsaturated” because it contains
less than the maximum possible amount of hydrogen.
When the two hydrogen atoms left, they took their electrons
with them, so now the C’s don’t have octets anymore.
HC CH
H H
The unpaired valence electrons that used to be paried with
the electrons from the missing hydrogens have now paired
with each other.
A double bond has formed between the two carbon atoms.
HC CH
H H
You can make an organic molecule even more unsatured by
removing even more hydrogen.
HC CH
You can make an organic molecule even more unsatured by
removing even more hydrogen.
As before, the unpaired electrons pair with each other to form
another bond. The double bond becomes a triple bond.
HC CH
You can make an organic molecule even more unsatured by
removing even more hydrogen.
As before, the unpaired electrons pair with each other to form
another bond. The double bond becomes a triple bond.
H
H
H
H
H C H
C
C
H C H
C
C
H
H
H
H
ethane ethene ethyne
Below is the skeletal formula of stearic acid, a “fatty acid”.
There are no carbon-carbon double bonds in this molecule’s
backbone, so it is “saturated”.
Because of the regular zig-zag pattern in the molecule, it is,
overall, fairly straight. Stearic acid molecules stick together
easily because of this.
Even in nonpolar
molecules like
fatty acids, weak
intermolecular
attractions called
“London forces”
become powerful
enough to cause
solidification
when long,
straight
molecules
snuggle up next
to each other.
Like other saturated fats, stearic
acid solidifies relatively easily, so
it is more likely to form arteryclogging atherosclerotic plaques
that can cause heart attacks and
strokes.
Below is the skeletal formula of oleic acid, another “fatty
acid”.
What’s this?
Oleic acid has one carbon-carbon double bond, so it is
considered to be “monounsaturated”.
The double bond in oleic acid makes the molecule bent.
Therefore, it is harder for it to solidify, so it’s less likely to
cause atherosclerotic plaque.
Ni
+ H2
Saturation of fatty acids by
nickel-catalyzed “hydrogenation”
can turn liquid oils into solid margarine.
And now,
a little review . . .
[remove all
rectangles]
[click bonds
me]
1. A carbon atom typically makes four covalent
[click me]
2. Carbon can form small molecules, or it can form long chains.
[click me]
3. The carbon “backbone”
of an organic molecule can be single[click me]
stranded or branched.
[click me]
[click me]
4. Carbon can form covalent
bonds with lots of nonmetal
[click
[click
[click me]
[click me]
elements such as hydrogen,
oxygen,
nitrogen,
sulfur,
and all the
me]
me]
[click me]
halogens.
[click
[click
[click me]
5. A carbon atom can form single,
double,
or
even
triple
bonds.
me]
me]
[click
[click me]
6. Double
bonds have different bonding angles than single
bonds,
me]
[click me]
[click me]
so saturated
and unsaturated
compounds have different fluidities.
1. A carbon atom typically makes four covalent bonds
2. Carbon can form small molecules, or it can form long chains.
3. The carbon “backbone” of an organic molecule can be singlestranded or branched.
4. Carbon can form covalent bonds with lots of nonmetal
elements such as hydrogen, oxygen, nitrogen, sulfur, and all the
halogens.
5. A carbon atom can form single, double, or even triple bonds.
6. Double bonds have different bonding angles than single bonds,
so saturated and unsaturated compounds have different fluidities.
Great. Carbon is super duper!
Now, make sure you learn the basics about
polymers, especially proteins, complex
carbohydrates, and nucleic acids.
Bye-bye now! All that follows is
construction site trash.
C
H
C
C C C C