1. Chapter 24 Organic Chemistry
24.1 Classes of Organic compounds
24.2 Alphatic hydrocarbons
Alkane
cycloalkane
Alkenes
Alkynes
Aromatic hydrocarbon
Chemistry of functional groups
Alcohol , ethers , aldhyde and ketones ,carboxylic acid , esters
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2. 24.1 Classes of Organic compounds
The chemistry of carbon compounds.
Carbon has the ability to form long chains and ring structure.
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3. 24.2 Alphatic hydrocarbons
Alkanes have the general formula CnH2n+2 where n = 1,2,3,…
only single covalent bonds (C-C), sp3 hybridization
saturated hydrocarbons because they contain the maximum number of hydrogen atoms that can bond with the number of carbon atoms in the molecule.
Boiling point increase with increase molecular size because of the increasing dispersion.
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4. 24-2
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5. Alkanes Nomenclature
IUPAC International Union of Pure and Applied Chemistry.
each name consist of 3 parts
prefix
indicates position (1,3,…etc.) , number (di,tri, tetra …etc.) and type of branches (alkyl or substituent groups table 24-3)
parent
indicates the length of the longest carbon chain or ring
suffix
indicates the type of hydrocarbon
ane, ene, yne
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6. 24-2
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7. CH3 CH CH2 1 2 3 4 5 4-methylpentane 1 2 3 4 5 2-methylpentane CH3 CH
Use prefixes di-, tri-, tetra-, when there is more than one alkyl branch of the same kind.
CH3 CH
CH2 1 2 3 4 5 6
CH3 CH C
CH2 1 2 3 4 5 6
2,3-dimethylhexane
3,3-dimethylhexane
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8. 2-bromo-5-methylhexane
CH3 CH
CH2 Br
2-bromo-5-methylhexane
CH3 CH Br 1 2 3 4
NO2
2-bromo-3-nitrobutane
CH2
3-bromo-1-nitrobutane
The substituent group are listed alphabetically
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9. Dr.Laila Al-Harbi

10. Dr.Laila Al-Harbi

11. What is the IUPAC name of the following compound?
CH3 CH
CH2
C2H5 1 2 3 4 5 6 7 8
4-ethyl-2-methyloctane
What is the structure of 2-propyl-4-methylhexane? 1 2 3 4 5 6
CH3 CH
CH2
C3H7
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12. DRAWING ORGANIC MOLECULES
Molecular formulae: A molecular formula simply counts the numbers of each sort of atom present in the molecule, but tells you nothing about the way they are joined together.
Example:
the molecular formula of butane is C4H10, and the molecular formula of ethanol is C2H6O.
Structural formulae: A structural formula shows how the various atoms are bonded.
ethanoic acid would be shown in a fully displayed form and asimplified form as:
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13. Structural Isomers in Alkanes
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14. Example 24.1 How many structural isomers does pentane, C5H12, have? H
n-pentane
2,2-dimethylpropane C H
CH3
2-methylbutane
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15. Reactions of Alkanes
Alkane not very reactive
1-Combustion ( exothermic)
CH4 (g) + 2O2 (g) → CO2 (g) + 2H2O (l) ∆H0 = kJ
2C2H6 (g) + 7O2 (g) → CO2 (g) + 6H2O (l) ∆H0 = kJ
2- Halogenations
CH4 (g) + Cl2 (g) CH3Cl (g) + HCl (g)
light
If an excess of chlorine gas is present, the reaction can proceed further:
CH3Cl(g) + Cl2(g) → CH2Cl2(l) + HCl(g)
methylene chloride
CH2Cl2(l) + Cl2(g) → CHCl3(l) + HCl(g)
chloroform
CHCl3(l) + Cl2(g) → CCl4(l) + HCl(g)
carbon tetrachloride
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16. Cycloalkanes
Alkanes whose carbon atoms are joined in rings are called cycloalkanes.
The general formula is Cn H2n where n = 3,4,… ( cycloalkane)
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17. Alkenes 2-butene 1-butene Cracking Geometric isomers of alkenes
Alkenes have the general formula CnH2n where n = 2,3,… (sp2)
contain at least one carbon-carbon double bond ( also called olefins)
CH2 CH
CH3
CH3 CH
2-butene
1-butene
Cracking
C2H6 (g) CH2 = CH2 (g) + H2 (g) Pt
catalyst
Geometric isomers of alkenes
cis-dichloroethylene
trans-dichloroethylene C Cl H C Cl H
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18. Which of the following compounds has geometrical isomer ?Cl C H Cl
NO ,Geometrical isomer
NO ,Geometrical isomer C
NO2 Cl H C
NO2 Cl H
yes ,it has geometrical isomer
NO ,Geometrical isomer C Cl H
yes ,it has geometrical isomer
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19. Alkenes Reactions Addition Reactions CH2 = CH2 (g) + Br2 (g) →
CH2B - CH2Br (g)
CH2 = CH2 (g) + HBr (g)
CH3- CH2Br (g)
Symmetrical alkene
unsymmetrical alkene
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20. Alkynes Alkynes have the general formula CnH2n-2 where n = 2,3,4,…
contain at least one carbon-carbon triple bond (sp)
CH3 C CH C
CH2
CH3
2-butyne
1-butyne
Production of acetylene
CaC2 (s) + 2H2O (l) → C2H2 (g) + Ca(OH)2 (aq)
Alkynes Reactions
3-oxidation
1-Hydrogenation
CH ≡ CH (g) + H2 (g)→
CH2 ≡CH2 (g)
2C2H2 (g) + O2 (g)→ 4CO2 +2H2O
2-Addition Reactions
4-decomposition
CH ≡ CH (g) + HBr (g) →
CH2 ≡ CHBr (g)
C2H2 (g) → 2C(s) + H2 (g)
CH ≡CHCH3 (g) + HBr (g) →
CH2=CHCH3 (g) Br -
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21. Aromatic Hydrocarbons
Aromatic compound contain one or more benzene ring C H
Aromatic Compound Nomenclature
If one H atom has been replaced by another atom or a group of atom >>the name of the atom or group then benzene
CH2CH3 Cl
chlorobenzene
NH2
NO2
nitrobenzene
ethylbenzene
aminobenzene
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22. Aromatic Compound Nomenclature
If more than one substituent is present >>we must indicate the location of the second group relative to first then benzene Br Br Br 1 2 3 4 5 6 Br
1,2-dibromobenzene
1,3-dibromobenzene
1,4-dibromobenzene
o-dibromobenzene
m-dibromobenzene
p-dibromobenzene
NO2 Br
CH3-CH-CH3
m-bromonitrobenzene
2-phenylpropane
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23. Aromatic Compound Reactions
1- Substitution reaction H Br
+ HBr
+ Br2
FeBr3
catalyst H
CH2CH3
+ HCl
+ CH3CH2Cl
AlCl3
catalyst
2- hydrogenation Pt
catalyst
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24. 25.3 Proteins
Polymers are large molecules made up of repeating units called Monomers
Proteins are polymers of amino acids ; they play a key role in nearly all biological process. Proteins high molar mass; ranging from about 5000 g.
The basic structural unit of protein is amino acids
Amino acid is a compound that contains at least one amino group(-NH2) and at least one carboxyl group(-COOH)
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25. Structure – an amino acid possesses both a carboxyl and an amino
group. The most common in the biological amino acids are the a-amino acids. The amino acid exists as a dipolar ion , possessing both a positive charge and a negative charge.
Dipolar ion
20 different amino acids are the building blocks of all proteins in the human body
The amino group of one molecule condenses with the acid group of another to gives Protein through peptide bonds
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26. Functional Group Chemistry
Term used to refer to parts of organic molecules where reactions tend to occur.
Compounds
Functional gp.
Comments
1-alcohol
R-OH
2-Ethers
R-O-R’
R=R’ , R≠ R’
R (Hydrocarbon , aromatic )
3-ketone
4-aldhyde
5-carboxilic acid
6- ester
7- amine
R3N
R2NH , RNH2
8-Amino acid
R - C – R’ O =
R - C - H O =
R - C - OH O =
R - C – OR’ O =
R-CH - C - OH O =
NH2 -
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27. Classify each of the following molecules as alcohol, aldehyde, ketone, carboxylic acid, amine, ether or amino acid.
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