My organic chemistry notes (1 Viewer)

[psych_girl]

Summary of Organic Chemistry I Basic ideas

The chemistry of carbon and its compounds is called organic chemistry.

Its properties:
· Each carbon atom has four outer shell valence electrons and can share these four valence electrons forming covalent bonds.
· Carbon’s covalent bonds can be single, double or triple bonds, e .g.: CH4, C2H4, C2H2.
· Carbon atoms can join to form chains or rings.
· Carbon atoms can share their valence electrons with other non-metal, such as H2, O2, Cl2 etc

Naming:
C1: meth- C2: eth- C3: prop- C4: but- C5: pent-
C6: hex- C7: hept- C8: oct- C9: non- C10: dec-

Rules for Naming
1. Alkanes:
· Find the longest chain of carbon atoms in the molecule.
· Name any branch (side) chains as the alkyl groups
· Number the side chains from the end of the parent chain, which will give them the lowest number.
· When there is more than one side chain, they are listed alphabetically.
· If the same side chain occurs more than once, prefixes di-tri-tetra-are used.

Example:
a. Name the compound drawn below:
CH3—CH—CH2—CH—CH2—CH3

CH3 CH2—CH3
Answer: 4-ethyl-2-methyl hexane

b. Name the compound drawn below:
CH3

CH3—CH2—CH2—C—CH3

CH3
Answer: 2,2-dimethyl pentane



2. Alkenes:
· Choose the longest consecutive chain of carbon atoms that includes the double bond, and name it as the parent alkene.
· Number the chain from the end that gives the double bond its smaller number.
· Name and number the alkyl groups as with the alkanes.

Example: Name the compound below:

CH3—CH—CH=CH2

CH3
Answer: 3-methyl-1-butene

3. Haloalkanes:
· Prefixes bromo-, chloro-, fluoro- and iodo-are used with the parent hydrocarbon.
· The carbon chain is numbered so that halogen atom has the smallest possible number.
· In the case of polyhalogen compounds:
(a) If only type of halogen atom is present, each is
numbered, and di-, tri-, etc. are used.
(b) If more than one type of halogen atom is present,
they are listed alphabetically as in 1.
Since the halogen atoms are functional groups, they are
numbered in preference to any side chains.

Example: Name the compound listed as following:
CH3—CH—CH—CH—CH—CH3

Cl Br Cl CH3
Answer: 3-bromo-2,4-dichloro-5-methylbexane

4. Alkanols:
· Choose the longest consecutive chain of carbon atoms which contains the –OH group.
· Number the chain from the end that gives the –OH group its smallest number.
· Name and number the functional groups as with the alkenes.

Example: Name the compound listed as following:
CH3—CH—CH3

OH
Answer: 2-methyl-2-propanol
Naming of carbon compounds:
Type of compound Gen.mol.formula prefix suffix Functional group Example name
Alkane CnH2n+2 -ane Alkyl group EthaneCH3—CH3
Alkene CnH2n -ene Double bond EthaneCH2=CH2
Alkyne CnH2n-2 -yne Triple bond Ethyne
Cycloalkane CnH2n Cyclo- Carbon Cyclopropane
Cycloalkene CnH2n-2 -ene Double Cyclohexene
Alkanol CnH2n+1OH -ol -OH Ethaol
haloalkanes CnH2n+1X -ane -X Chloromethane

Summary of organic chemistry II

General properties of alkanes and alkenes

Physical properties:

· Both have low melting point

· Both have low boiling point

Chemical properties:

· Combustion: They both burn in a plentiful supply of air to form carbon dioxide and water. However, alkenes are more reactive than alkanes because they have a double bond. This greater reactivity allows alkenes to undergo addition reactions, whereas alkanes undergo substitution reactions.

· Addition reactions: Alkenes undergo addition reactions with hydrogen and other non-metals. They react by breaking the double bond and adding in other atoms. Addition reactions can only occur in unsaturated compounds. Alkanes can’t undergo addition reactions as they are not as reactive as alkenes. They do not have a double bond. Ethane reacts with hydrogen by an addition reaction.

· Substitution Reactions: Alkanes undergo substitution reactions. Other atoms can replace a hydrogen atom, substituting another atom for the hydrogen. Substitution reactions occur in saturated compounds. Halogen (group VII) elements can substitute into alkanes in this way.

Haloalkanes—Physical and chemical properties:

Physical properties:

· Resmble those of the alkanes, but B.P. are higher.

· They are immiscible to water

· Are used as solvents for fats and oils.

Preparation:

They can be prepared by treating an alkene with a
hydrogen halide. This is an addition reation.

General equation:
R-CH=CH2+HX RCHXCH3

Chemical properties:

· They react with aqueous NaOH or KOH to form alkanol. This is a substitution reaction.

General equation:
R-X+KOH R-OH+KX

· They react more vigorously with alcohol in NaOH or KOH to form the corresponding alkene, this is an elimination reaction.

General equation:
R-CH2—CH2—Br+KOH R—CH=CH2+KBr+H2O

· They react with a sodium alkoxide to form ethers. Ethers are excellent solvents and were also the early anaesthetics.

General equation:
RONa+RX ROR+NaX

Reactions: With aqueous KOH ---alkanols (substitution)
With alcoholic KOH---alkenes (elimination)
With sodium alkoxides---ethers


Alkenes—physical and chemical properties:

Physical properties:

· Alkenes are non-polar compounds.

· The first four members are gases and the rest are low boiling point liquids.

Preparation:

· From the action of alcoholic KOH on the corresponding haloakkane.

· By the dehydrating action of the concentrated sulfuric acid or phosphoric acid on an alkanol. Tertiary alkanols are more readily converted to the corresponding alkene than secondary or primary alkanols.

Chemical properties:

· Combustion. Alkenes burn exothermally in air to form carbon dioxide and water.

General equation:
CnH2n+3n/2O2 nCO2+nH2O

· Alkenes undergo the following addition reactions.

1. Hydrogenation: The alkene is hanged to the corresponding alkane by heating the alkene and hydrogen while using a platinum or palladium catalyst.

General equation:

R-CH=CH2+H2 R-CH2—CH3

2. Halogenation: Halogen atoms add across the double bond.

General equation:

R-CH=CH2+Cl2 R-CHCl-CH2Cl



3. Hydrogen halides and alkenes:

General equation:

R-CH=CH2+HBr R-CHBr-CH3

4. Hydration: water reacts with an alkene in the presence of dilute sulfuric acid.

General equation:
dil
R-CH=CH2+H2O R-CHOH-CH3
H2SO4

5. Oxidation: alkenes are readily oxidized. If the KMnO4 solution is dilute. The following reactions will occur.

i. dil
R-CH=CH-CH3 R-CH-CH-CH3
KMnO4

ii. If the alkene is boiled with a concentrated solution of
potassium permanganate further oxidation occurs,
and if the alkene has a straight chain, the end
products will be alkanoic acids.

General equation: (not for 1-alkenes)
water heat
R-CH=CH-CH3 R-COOH+CH3—COOH

Reactions:

Undergo addition reactions with

1. Hydrogen

2. Halogens

3. HX (where X is any halide ion)

4. Water/ H+

5. oxidized gently by dilute KMnO4 to diols

6. Oxidized vigorously with concentrated KMnO4 to break the double bond.


Alkanols (alcohols)----Physical & chemical properties and its
Preparation

Alkanols are alcohols which are formed from alkanes. Alcohols refer to a wider group of compounds which all contain an –OH group.
It may be:

Primary: R-CH2-OH

R
Secondary: CH-OH
R’

R

Tertiary: R’—C--OH

R”
Where R- is any alkyl group

Physical properties:

· Because of hydrogen bonding, the alkanols have much higher boiling points than the corresponding alkanes.

· The molecules are polar and this results in the lower alkanols being soluble in water. However, as the carbon chain becomes longer, since it is non-polar, the higher alkanols are insoluble in water. Ethanol is an excellent solvent since it is miscible not only with water, but also with organic liquids. e.g. ethers.

Chemical properties:

· Combustion

Alcohols burn readily in air and are exothermic.

Reaction with sodium metal

This is a very important reaction for alcohols since it shows that one hydrogen atom, the one in -OH group, is bonded differently from the other hydrogen atoms in the alcohol molecule.

General equation:

2ROH+2Na 2RONa+H2

· Dehydration

Alcohols lost water to form alkenes when heated with concentrated sulfuric acid. The concentration H2SO4 absorbs the water as it is formed.

General equation:

concentration
R-CH2-CH2-OH R-CH=CH2
H2SO4
N.B. reaction: Alkanols---Alkenes

· Oxidation

These reactions can distinguish between primary, secondary and tertiary alcohols.

The position of the –OH group determines the yupe of reaction.

a. Primary alcohols have an –OH group on a terminal carbon atom, R-CH2-OH. On oxidation by acidified potassium permanganate or potassium dichromate they first form the alkanals which are readily oxidized in turn to alkanoic acid.
b. Secondary alcohols. These are oxidized by potassium permanganate and potassium dichromate in acid solutions. They contain a –CHOH group, which can’t be on a terminal carbon atom.
[O]
Secondary alkanols alkanones
c. Tertiary alkanols. These are not oxidized under usual conditions.


· Esterification

Alcohols react with alkanoic acids in the presence of a small amount of concentrated sulfuric acid to form esters.

General equation:

R-OH+R’-COOH R’-COO-R+H2O

· Reaction with hydrogen halides (also PCl3 and PBr3)

This is a substitution reaction.

General equation:
R-OH+HX R-X+H2O
&
3R-OH+PX3 3R-X+H3PO3

Preparation:

· In the laboratory

(i) By a substitution reaction with aqueous KOH.

General equation:

RCl+KOH ROH+KCl

(ii) By hydration of alkenes

General equation:

ROH=CH2+H2O RCHOHCH3

· Commercial preparations

Methanol. This can be prepared by the destructive
distillation of wood. On an industrial level. It is prepared by
passing a mixture of carbon monoxide and hydrogen over a
metal catalyst at high temperature and pressure.

Ethanol. This can be produced from grains and sugars by a
fermentation process using yeast. The enzymes in yeast act
as catalysts which change glucose to ethanol. The process
ceases when the ethanol produced reach a level high
enough to kill the ethanol produced by fermentation
processes are used in beer and wine.

Summary of carbon chemistry: III
Supplementary notes:
The arrangement of atoms around a particular carbon atom is as follows:
· Carbon forms four single bonds resulting in a tetrahedral shape.
· Carbon forms one doule and two single bonds resulting in a planar shape.
· Carbon forms one triple and one single bond resulting in a planar shape.
Some simple bonding rules for carbon-based compounds are as follows:
· Carbon atoms must form four bonds.
· Halogen atoms must form one bond.
· Oxygen atoms much form two bonds.
· Nitrogen atoms must form tree bonds.
· Hydrogen atoms must form one bond.















The traditional and systematic (IUPAC) names of some common organic compounds.
Traditional name IUPAC name Formula
Ethylene Ethane CH2CH2
Acetylene Ethyne CHCH
Formaldehyde Methanal HCHO
Acetaldehyde Ethanal CH3CHO
Acetone Propanone CH3COCH3
Formic acid Methanoic acid HCOOH
Acetic acid Ethanoic acid CH3COOH
Oxalic acid Ethanedioic acid HOOCCOOH
Vinyl chloride Chloroethene CH2CHCl
Chlorform Trichloromethane CHCl3
Carbon tetrachloride Tetrachloromethane CCl4
glycerol 1,2,3-propanetriol CH2OHCHOHCH2OH

 

[psych_girl]

Summary of Organic Chemistry I Basic ideas

The chemistry of carbon and its compounds is called organic chemistry.

Its properties:
· Each carbon atom has four outer shell valence electrons and can share these four valence electrons forming covalent bonds.
· Carbon’s covalent bonds can be single, double or triple bonds, e .g.: CH4, C2H4, C2H2.
· Carbon atoms can join to form chains or rings.
· Carbon atoms can share their valence electrons with other non-metal, such as H2, O2, Cl2 etc

Naming:
C1: meth- C2: eth- C3: prop- C4: but- C5: pent-
C6: hex- C7: hept- C8: oct- C9: non- C10: dec-

Rules for Naming
1. Alkanes:
· Find the longest chain of carbon atoms in the molecule.
· Name any branch (side) chains as the alkyl groups
· Number the side chains from the end of the parent chain, which will give them the lowest number.
· When there is more than one side chain, they are listed alphabetically.
· If the same side chain occurs more than once, prefixes di-tri-tetra-are used.

Example:
a. Name the compound drawn below:
CH3—CH—CH2—CH—CH2—CH3

CH3 CH2—CH3
Answer: 4-ethyl-2-methyl hexane

b. Name the compound drawn below:
CH3

CH3—CH2—CH2—C—CH3

CH3
Answer: 2,2-dimethyl pentane



2. Alkenes:
· Choose the longest consecutive chain of carbon atoms that includes the double bond, and name it as the parent alkene.
· Number the chain from the end that gives the double bond its smaller number.
· Name and number the alkyl groups as with the alkanes.

Example: Name the compound below:

CH3—CH—CH=CH2

CH3
Answer: 3-methyl-1-butene

3. Haloalkanes:
· Prefixes bromo-, chloro-, fluoro- and iodo-are used with the parent hydrocarbon.
· The carbon chain is numbered so that halogen atom has the smallest possible number.
· In the case of polyhalogen compounds:
(a) If only type of halogen atom is present, each is
numbered, and di-, tri-, etc. are used.
(b) If more than one type of halogen atom is present,
they are listed alphabetically as in 1.
Since the halogen atoms are functional groups, they are
numbered in preference to any side chains.

Example: Name the compound listed as following:
CH3—CH—CH—CH—CH—CH3

Cl Br Cl CH3
Answer: 3-bromo-2,4-dichloro-5-methylbexane

4. Alkanols:
· Choose the longest consecutive chain of carbon atoms which contains the –OH group.
· Number the chain from the end that gives the –OH group its smallest number.
· Name and number the functional groups as with the alkenes.

Example: Name the compound listed as following:
CH3—CH—CH3

OH
Answer: 2-methyl-2-propanol
Naming of carbon compounds:
Type of compound Gen.mol.formula prefix suffix Functional group Example name
Alkane CnH2n+2 -ane Alkyl group EthaneCH3—CH3
Alkene CnH2n -ene Double bond EthaneCH2=CH2
Alkyne CnH2n-2 -yne Triple bond Ethyne
Cycloalkane CnH2n Cyclo- Carbon Cyclopropane
Cycloalkene CnH2n-2 -ene Double Cyclohexene
Alkanol CnH2n+1OH -ol -OH Ethaol
haloalkanes CnH2n+1X -ane -X Chloromethane

Summary of organic chemistry II

General properties of alkanes and alkenes

Physical properties:

· Both have low melting point

· Both have low boiling point

Chemical properties:

· Combustion: They both burn in a plentiful supply of air to form carbon dioxide and water. However, alkenes are more reactive than alkanes because they have a double bond. This greater reactivity allows alkenes to undergo addition reactions, whereas alkanes undergo substitution reactions.

· Addition reactions: Alkenes undergo addition reactions with hydrogen and other non-metals. They react by breaking the double bond and adding in other atoms. Addition reactions can only occur in unsaturated compounds. Alkanes can’t undergo addition reactions as they are not as reactive as alkenes. They do not have a double bond. Ethane reacts with hydrogen by an addition reaction.

· Substitution Reactions: Alkanes undergo substitution reactions. Other atoms can replace a hydrogen atom, substituting another atom for the hydrogen. Substitution reactions occur in saturated compounds. Halogen (group VII) elements can substitute into alkanes in this way.

Haloalkanes—Physical and chemical properties:

Physical properties:

· Resmble those of the alkanes, but B.P. are higher.

· They are immiscible to water

· Are used as solvents for fats and oils.

Preparation:

They can be prepared by treating an alkene with a
hydrogen halide. This is an addition reation.

General equation:
R-CH=CH2+HX RCHXCH3

Chemical properties:

· They react with aqueous NaOH or KOH to form alkanol. This is a substitution reaction.

General equation:
R-X+KOH R-OH+KX

· They react more vigorously with alcohol in NaOH or KOH to form the corresponding alkene, this is an elimination reaction.

General equation:
R-CH2—CH2—Br+KOH R—CH=CH2+KBr+H2O

· They react with a sodium alkoxide to form ethers. Ethers are excellent solvents and were also the early anaesthetics.

General equation:
RONa+RX ROR+NaX

Reactions: With aqueous KOH ---alkanols (substitution)
With alcoholic KOH---alkenes (elimination)
With sodium alkoxides---ethers


Alkenes—physical and chemical properties:

Physical properties:

· Alkenes are non-polar compounds.

· The first four members are gases and the rest are low boiling point liquids.

Preparation:

· From the action of alcoholic KOH on the corresponding haloakkane.

· By the dehydrating action of the concentrated sulfuric acid or phosphoric acid on an alkanol. Tertiary alkanols are more readily converted to the corresponding alkene than secondary or primary alkanols.

Chemical properties:

· Combustion. Alkenes burn exothermally in air to form carbon dioxide and water.

General equation:
CnH2n+3n/2O2 nCO2+nH2O

· Alkenes undergo the following addition reactions.

1. Hydrogenation: The alkene is hanged to the corresponding alkane by heating the alkene and hydrogen while using a platinum or palladium catalyst.

General equation:

R-CH=CH2+H2 R-CH2—CH3

2. Halogenation: Halogen atoms add across the double bond.

General equation:

R-CH=CH2+Cl2 R-CHCl-CH2Cl



3. Hydrogen halides and alkenes:

General equation:

R-CH=CH2+HBr R-CHBr-CH3

4. Hydration: water reacts with an alkene in the presence of dilute sulfuric acid.

General equation:
dil
R-CH=CH2+H2O R-CHOH-CH3
H2SO4

5. Oxidation: alkenes are readily oxidized. If the KMnO4 solution is dilute. The following reactions will occur.

i. dil
R-CH=CH-CH3 R-CH-CH-CH3
KMnO4

ii. If the alkene is boiled with a concentrated solution of
potassium permanganate further oxidation occurs,
and if the alkene has a straight chain, the end
products will be alkanoic acids.

General equation: (not for 1-alkenes)
water heat
R-CH=CH-CH3 R-COOH+CH3—COOH

Reactions:

Undergo addition reactions with

1. Hydrogen

2. Halogens

3. HX (where X is any halide ion)

4. Water/ H+

5. oxidized gently by dilute KMnO4 to diols

6. Oxidized vigorously with concentrated KMnO4 to break the double bond.


Alkanols (alcohols)----Physical & chemical properties and its
Preparation

Alkanols are alcohols which are formed from alkanes. Alcohols refer to a wider group of compounds which all contain an –OH group.
It may be:

Primary: R-CH2-OH

R
Secondary: CH-OH
R’

R

Tertiary: R’—C--OH

R”
Where R- is any alkyl group

Physical properties:

· Because of hydrogen bonding, the alkanols have much higher boiling points than the corresponding alkanes.

· The molecules are polar and this results in the lower alkanols being soluble in water. However, as the carbon chain becomes longer, since it is non-polar, the higher alkanols are insoluble in water. Ethanol is an excellent solvent since it is miscible not only with water, but also with organic liquids. e.g. ethers.

Chemical properties:

· Combustion

Alcohols burn readily in air and are exothermic.

Reaction with sodium metal

This is a very important reaction for alcohols since it shows that one hydrogen atom, the one in -OH group, is bonded differently from the other hydrogen atoms in the alcohol molecule.

General equation:

2ROH+2Na 2RONa+H2

· Dehydration

Alcohols lost water to form alkenes when heated with concentrated sulfuric acid. The concentration H2SO4 absorbs the water as it is formed.

General equation:

concentration
R-CH2-CH2-OH R-CH=CH2
H2SO4
N.B. reaction: Alkanols---Alkenes

· Oxidation

These reactions can distinguish between primary, secondary and tertiary alcohols.

The position of the –OH group determines the yupe of reaction.

a. Primary alcohols have an –OH group on a terminal carbon atom, R-CH2-OH. On oxidation by acidified potassium permanganate or potassium dichromate they first form the alkanals which are readily oxidized in turn to alkanoic acid.
b. Secondary alcohols. These are oxidized by potassium permanganate and potassium dichromate in acid solutions. They contain a –CHOH group, which can’t be on a terminal carbon atom.
[O]
Secondary alkanols alkanones
c. Tertiary alkanols. These are not oxidized under usual conditions.


· Esterification

Alcohols react with alkanoic acids in the presence of a small amount of concentrated sulfuric acid to form esters.

General equation:

R-OH+R’-COOH R’-COO-R+H2O

· Reaction with hydrogen halides (also PCl3 and PBr3)

This is a substitution reaction.

General equation:
R-OH+HX R-X+H2O
&
3R-OH+PX3 3R-X+H3PO3

Preparation:

· In the laboratory

(i) By a substitution reaction with aqueous KOH.

General equation:

RCl+KOH ROH+KCl

(ii) By hydration of alkenes

General equation:

ROH=CH2+H2O RCHOHCH3

· Commercial preparations

Methanol. This can be prepared by the destructive
distillation of wood. On an industrial level. It is prepared by
passing a mixture of carbon monoxide and hydrogen over a
metal catalyst at high temperature and pressure.

Ethanol. This can be produced from grains and sugars by a
fermentation process using yeast. The enzymes in yeast act
as catalysts which change glucose to ethanol. The process
ceases when the ethanol produced reach a level high
enough to kill the ethanol produced by fermentation
processes are used in beer and wine.

Summary of carbon chemistry: III
Supplementary notes:
The arrangement of atoms around a particular carbon atom is as follows:
· Carbon forms four single bonds resulting in a tetrahedral shape.
· Carbon forms one doule and two single bonds resulting in a planar shape.
· Carbon forms one triple and one single bond resulting in a planar shape.
Some simple bonding rules for carbon-based compounds are as follows:
· Carbon atoms must form four bonds.
· Halogen atoms must form one bond.
· Oxygen atoms much form two bonds.
· Nitrogen atoms must form tree bonds.
· Hydrogen atoms must form one bond.















The traditional and systematic (IUPAC) names of some common organic compounds.
Traditional name IUPAC name Formula
Ethylene Ethane CH2CH2
Acetylene Ethyne CHCH
Formaldehyde Methanal HCHO
Acetaldehyde Ethanal CH3CHO
Acetone Propanone CH3COCH3
Formic acid Methanoic acid HCOOH
Acetic acid Ethanoic acid CH3COOH
Oxalic acid Ethanedioic acid HOOCCOOH
Vinyl chloride Chloroethene CH2CHCl
Chlorform Trichloromethane CHCl3
Carbon tetrachloride Tetrachloromethane CCl4
glycerol 1,2,3-propanetriol CH2OHCHOHCH2OH

Hope these notes can help ppl with "energy" section in yr 11

 

[Slidey]

LOL. This stuff is in the energy topic of prelim? That would explain why I found HSC Production of Materials hard at first.

Now I'm cruising, though.

 

[psych_girl]

->

lol..........It is also the basic knowledge to understand organic chemistry. but for yr 11, it is bit easier.

 

[Slidey]

Yeah, well, our teacher only taught 3 modules, not 4 - we never learnt the Energy module in year 11.

OH, BTW, you should put your notes in a word document and submit them to BOS on the main site. More people will see/have access to your notes that way.

 

[psych_girl]

--->

Beacuse i cant put my note on the site. Coz the computer problem...........

 

[Slidey]

Still, keep them in a word doc and upload them when it is fixed.

 

[paganinio]

cool, I'm studying organic chem since yesterday

 

[esp_d]

hay thnx 4 the notes!....we studied tht at sch. 2day, it was supposed to b like revision and like the whole class knew it all....but i was like totally lost cus my yr 10 sci teacher tought jackshit and im at a new sch where evry1s soo brainy and kno evrything

anywayz thnx again

 

[-neurosurgeon-]

thanks! i needed to know how to name the compounds....my year 10 teacher couldn teach either...errgh -_-"

 

[katykins]

wow
thnx a bundle!!

 

[[Damo]]

Hey, any1 done the 2005 Independant Preliminary trial?? i want to use it to study, you you could send it, much appreciated

 

[kylie2468]

hey if anyone has prelim chem notes could they please send them to me, i would be so greatful lost_ones_86hope@hotmail.com

pleaseeee im a damsel in distress

 

[rahulbedi]

awesome, thanks

 

[lovelywhite]

haha.

I just finished my organic chemistry in-class test, uni chemitry is much more tough than high school. especialy inorganic. my headache....:mad1:

 

[hilbot]

I just need to find out one thing. When you have reactions between cyclohexanes, cyclohexenes and bromine, you get a layer on top of the clear liquid. Why does that layer form?

Any ideas would be great.