Chemistry Form 5 Module Organic Compound

CHAPTER 2: CARBON COMPOUNDS

B. 2.0 1. Write the general formula of alkenes. 2. Explain why boiling point of alkenes increase descending the homologous series 3. Write the equation of combustion of pentene

1. Write the formula of alkane. 2. Explain why boiling point of alkanes increase descending the homologous series 3. Write the equation of combustion of pentane

1. Define the carbon compound. 2. What is an organic compound? 3. List 3 examples of organic compound and 3 examples of nonorganic compound.

Alkane Carbon compound

Alkenes 2.2

2.3

2.1

Isomerism

2.4 1. Define polymer. 2. Explain the coagulation process of latex when it is added with formic acid. 2. Explain why vulcanized rubber is stronger than natural rubber.

Natural2.9 rubber

CARBON COMPOUND

2.8

2.5 2.7

2.6

Alcohol

Fat Ester 1. Define saturated fat and unsaturated fat. 2. Stated the difference between saturated fat and unsaturated fat. 3. What is the type of reaction that changes unsaturated fat to saturated fat?

1. Define isomerism 2. Draw structural formula of pentane isomers 3. Draw structural formula of pentene isomers

1. Define the homologous series of alcohol 2. Write the chemical equation of combustion of propanol. 3. Describe a laboratory experiment to produce alcohol

Carboxylic acid

1. Define an ester. 2. Write the general formula of ester. 3. Describe an experiment to produce etil methanoic.

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1. Define carboxylic acid. 2. Write the equation involved in the production of carboxylic acid from propanol. 3. Explain why methanoic acid cannot conduct an electric

B. 2.1

Compound consists of carbon element.

Definition of carbon compound

Examples ORGANIC CARBON COMPOUND

Combustion of organic compounds sebatian organik

Type of compound Saturated hydrocarbon s

Hydrocarbon

Examples; .

Inorganic compound

Unsaturated hydrocarbon s

Inorganic carbon compound

Organic carbon compound

Compounds contain carbon and come from organism (living thing). Animal or plants

Examples: Glucose, Protein, Fat, etc

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Compound consists of carbon and did not come from the organism (animal or plant)

Examples: Carbonate of metal, Bicarbonate of metal, carbon dioxide, carbon monoxide, etc

B. 2.2 n

Molecular formula

Name

Structural formula

1

CH4

methane

2

C2H6

ethane

……..

3

……..

propane

……….

4

C4H10

butane

5

………

pentane

Members Methane Ethane Propane Butane Pentane Hexane

Size of molecule Small

Melting point Low

Density

State

Low

Increase

Increase

Increase

Gas Gas Gas Gas Liquid Liquid

………

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Physical properties and the changes

General formula and group members

General formula

1. Non soluble in water 2. Non conductor of electricity

Explanation to the physical properties change.

Non complete combustion

ALKANE CnH2n +2 n = 1,2,3,…

CH4 + O2

C + 2H2O

C2H6 + O2

…. + …..

…… + ….. Substitution reactions

Chemical properties

Sun light CH4 + Cl2

CH2Cl2 + ……..

Combustion

CH3Cl + HCl

CH3Cl + Cl2 Cl2

+ …….

…. + …

CH2Cl2 + HCl ……..

Complete combustion.

+ ……

……… + …….

CH4 + O2

CO2 + 2H2O

C2H6 + O2

……

C4H10 + O2

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+ ……

…….. + …….

n

Molecular Formula

Name

1

C2H4

ethene

2

C3H6

propene

3

……..

butene

4

C5H10

pentene

5

………

hexene

B. 2.3

Structural Formula

Members Ethene Propene Butene Pentene Hexene Heptene

Molecul ar size

Increase

10

General formula CnH2n n = 2.3,4, …

Physical properties and the changes

General formula and group members Homologous Series

Test to differentiate alkenes using bromine water /Acidic potassium magnate (VII). Experiment.

Melting point Low

Density

State

Low

Increase

increase

Gas Gas Gas Gas Liquid Liquid

1. Non soluble in water 2. Non conductor of electricity

Explanation to the changes

ALKENE Chemical properties

Polymerization of alkene

Reaction

Examples

1. Addition reaction (a) Addition of hydrogen (hydrogenation)

C2H4

+ H2

(b) Addition of bromine

C3H6

(c) Addition of steam

C2H4

(d) Oxidation

C2H4

+ Br2 C3H6Br2 H3PO4, 300oC, 60 atm. + H2O C2H5OH acidic KMnO4 + H2O + [O] C2H6O2

2. Combustion Combustion in the air (oxygen)

C2H4 + 3O2 C4H8 + ……

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C2H6

2CO2 + 2H2O …….

+ ……

B.2.4 Isomers of pentane

Isomers of butene

Compound with the same molecular formula but different structural formula

IUPAC naming

Example of isomer Definition of isomerism ISOMERISM

IUPAC name of isomer

Instruction: 1. Specify the number of carbon atom in the longest continuous carbon chain. 2. Numbering carbon atoms with 1,2,3,… starting near functional group /and branch.. 3. Branch names -CH3 , methyl -CH2CH3, ethyl

Isomer of alkane (hexane)

Isomer of an alkene (pentene)

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B.2.5 CH3OH C2H5OH C3H7OH C4H9OH

Carbon compound contained hydroxyl functional group, OH

Misuse of the alcohol and the effect

methanol ethanol propanol butanol

Physical properties and the changes downward series.

Formula Am:

Fuel, solvent, Medical aspect, Cosmetic aspect..

CnH2n+ 1OH n = 1,2,3,…

Naming

Definition of alcohol Usage of alcohol

Homologous series of alcohol

Chemical properties of alcohol

ALCOHOL

Isomerism in the alcohol

Chemical properties of the ethanol 1. Combustion C2H5OH + O2 CO2 + H2O 2. Oxidation 2[O] C2H5OH CH3COOH + H2O

Ethanol

3. Dehydration Alumina C2H5OH C2H4 + H2O

The physical properties of the ethanol

Cotton + Ethanol

Alumina Ethene

Preparation of ethanol

Dissolve in water Dissolve in organic solvent, Neutral, Non-conductor of electricity

In industry: Steam + ethene

In laboratory: Fermentation Process. Experiment Diagram

Heat Water 15

Dehydration of ethanol B. 2.6

CnH2n+1COOH n = 0,1,2,…

HCOOH CH3COOH C2H5 COOH C3H7COOH C4H9COOH …………..

General formula

methanoic acid ethanoic acid propanoic acid butanoic acid pentanoic acid

Acid that contain the functional group carboxyl, -COOH

Homologous Series

Naming

O R -C - OH where R is an alkyl group

Oxidation of ethanol Acidic KMnO4 C2H5OH CH3COOH + H2O Conc. H2SO4

Definition

CARBOXYLIC ACID

Ketertiban dalam siri homolog

Preparation of ethanoic acid

Physical properties of the carboxylic acid karboksilik

The usage of carboxylic acid Chemical properties of ethanoic acid

1.

Ethanoic acid + base CH3COOH + NaOH

2. Ethanoic acid + carbonate 2CH3COOH + K2CO3 3. Ethanoic acid + metal 2CH3COOH + Mg 4. Ethanoic acid + alcohol Ethanoic + ethanol CH3COOH + C2H5OH

salt + water CH3COONa + H2O salt + water + carbon dioxide 2CH3COOK + H2O + CO2 salt + hydrogen (CH3COO)2Mg + H2 esther + water ethyl ethanoat + water CH3COOC2H5 + H2O

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Ethanoic acid + ethanol + concentrated sulphuric acid ( after boiling)

n

CnH2n+1COOCmH2m+1 n = 0,1,2,… m = 1,2,3,…

m

0

2

1

1

2

3

Molecular formula

Name of ester

General formula of ester Molecular formula and the name of ester Homologous series of ester A group of homologous series with functional group of carboxyl, -COO-

Definition

Diagram?

Preparation

ESTER Ethyl ethanoate etanoat Physical properties

The ester daily life usage Natural source of the ester

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To predict the formation of the ester

B. 5.3

…is an ester formed from glycerol (alcohol) and carboxylic acid. Definition

The fat molecule that built of only singular covalent bond between carbon atom in the molecules.

Definition

? fat and oil.

The fat molecules that built of multiple bond between carbon atom in molecules.

Examples: Chicken’s fat, Cow’s fat, Etc.

Saturated fat

definition Unsaturated fat

Contoh:

Comparison

Type of fat Fat Higher melting point (more than 20oC) Solid at room temperature Found in animals & human

Oil Lower melting point (less than 20oC) Liquid at room temperature Found in plants & fish

Conversion of the unsaturated fat to the saturated fat.

FAT AND OIL

The effect of fat on health Palm oil

Production of margerine: Hydrogenation process of unsaturated fat (palm oil) Ni - C = C - + H2

The needed to use palm oil

Extraction process of palm oil in industry

Double bond

Taken too much saturated fat may cause: 1. Obesity 2. Hardness of an artery 3. High blood pressure 4. Heart disease 5. Stroke

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-C – C – H H single bond

B. 5.4 R

O

R

O

R

n H2N - CH - C - OH + H - N - CH – C - OH

H amino acid (monomer)

Protein

nC6H12O6 glucose (monomer)

Giant molecule with long chain (macromolecule) consist of repeated sequence small molecules (micro molecule) called monomer found in an animal & plant

Definition of natural polymer Usage of natural rubber

Vulcanization of rubber.

O

H protein (polymer)

+ nH2O n

(C6H10O5)n + nH2O starch (polymer)

Carbohydrate

NATURAL RUBBER

Natural rubber

Comparing the properties of the natural and vulcanized rubber -- Explain

R

N - CH – C - N - CH – C -

H Amino acid (monomer)

O

Preventing coagulation of latex Definition

Several polymer and it’s monomer

nC5H8 Isoprene (monomer)

Coagulating of the latex

(C5H8)n natural rubber (polymer)

Experiment

Latex is a colloid. It is a mixture of rubber particles and water. A rubber particle is made up of negatively charged protein membrane surrounds many rubber molecules. The negative charges are preventing the collision between molecules. When an acid is added to the latex, H+ from an acid is neutralized the negative charge at protein membrane to allow the collision between the rubber particles. The protein membrane breaks, and then the rubber molecules are free to clump together. Latex has coagulated

Experiment: 1. Vulcanization of natural rubber. 2. Comparison of properties between natural and vulcanized rubber

Diagram 19

A. Analysing Alkanes 1. 2..

The general formula of alkanes are : ______________________________ Complete the table by writing the name , molecular formula and structural formula of alkanes. Number of Carbon atom per molecule

Molecular formula

Name

Structural formula

1 2 3

4

5

3.

All alkanes _______________________ in water because they are _____________________ compounds.

4.

As the number of carbon atoms increases, a)

the size of the molecule _____________________________

b)

the boiling and melting point ___________________ because _____________________ ________________________________________________________________________

c)

the amount of soot produced ______________________ because ___________________ ________________________________________________________________________

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5.

6.

Complete combustion of alkanes produces carbon dioxide and water only. a)

C2H6

+

O2



b)

C5H12 +

O2



Alkanes undergo substitution reaction with halogrns in the presence of ultra violet light. CH4

+

Cl2 

B. Analysing Alkenes 1. 2

The general formula for alkenes is __________________________________________ Complete the table below by writing the names, molecular formula and structural formula . Number of Carbon atom per molecule

Molecular formula

Name

Structural formula

2 3

4

3.

Alkenes undergo addition reaction due to the presence of the double bonds. a)

Hydrogenation : C3H6

+

H2



Condition of reaction : _________________________________ b)

Halogenation :

C3H6 -

+ Br2 C–

 C=C-

21

+

Br-Br 

d)

Hydration :

Condition of reaction : ____________________________________ e)

Oxidation :

4 . Polimerization : The process whereby small molecules are joined together to form large molecules. 5. Compare and contrast between alkanes and alkenes. Alkanes General Formula Bonding Combustion Physical properties

Chemical properties

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Alkenes

Flowchart for the reaction of ethene Ethane-1,2-diol C2H4(OH)2

Poliethene IV

II C2H5Cl

Ethanea C2H6

I

Ethene C2H4

III V 1,2 dibromoethane C2H4Br2

Ethanoic acid CH3COOH

VI

VII X

Carbon dioxide and water

Write the balanced equation for the processes labeled above. I

VI

II

VII

III

VIII

IV

IX

V

X

10

IX

VIII

Ethanol C2H5OH

Ethyl ethanoate CH3COOC2H5

Flowchart for the reaction of ethene Butane-1,2-diol C4H8(OH)2

Polibutene IV

II C4H9Cl

Butane C4H10

I

VI

Butene C4H8

III V 1,2 dibromobutane C4H8Br2

Butanoic Acid C3H7COOH

VII X

Carbon dioxide and water

Write the balanced equation for the processes labeled above.

I

VI

II

VII

III

VIII

IV

IX

V

X

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VIII

Butanol C4H9OH

IX

Butyl butanoate C3H7COOC4H9

Flowchart for the reaction of propene propane-1,2-diol C3H6(OH)2

Polipropene IV

II C3H7Cl

Propane C3H8

I

VI

Propena C3H6

III V 1,2 dibromopropane C3H6Br2

Propanoic acid C2H5COOH

VII X

Carbon dioxide and water

Write the balanced equation for the processes labeled above. I

VI

II

VII

III

VIII

IV

IX

V

X

12

VIII

Propanol C3H7OH

IX

Propyl propanoate C2H5COOC3H7

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Objective Questions 1.

What is the functional group for alcohol? A. Carboxylate B. C. Hydroxide D.

Diol Hydroxyl

2.

Which process is involved in changing propene into propanol ? A. Oxidation B. Hydration C. Fermentation D. Combustion

3.

The equation below representsthe reaction in the industrial preparation of ethanol. X + H2O  CH3CH2OH What is X ? A. C.

Ethene Glucose

B.

Ethane D. Maltose

4.

What are the products of the reaction between propanoic acid and sodium hydroxide ? A. water and carbon dioxide B. Ethyl ethanoate and sodium ethanoate C. Water and ethyl ethanoate D. Sodium ethanoate and water.

5.

Which of the following is not true about the difference between saturated fats and unsaturated fats A B C D

6.

Characteristic Melting Point Source Cholesterol content Physical state at room temperature

Saturated Fats Low Animals High Solid

Unsaturated fats High Plants Low Liquid

Coagulation of latex takes place by adding …. I formic acid II nitric acid III aqueous ammonia IV hydrochloric acid A. C.

I and II only I , II and III only

B.

II and III only D. I , II , III and IV.

7.

Vulcanised rubber is harder because….. A. the polymers of rubber are arranged orderly B. the polymers of rubber combine to form longer chains C. the polymers are held by sulphur linkage D. the polymers became neutral. Structural Questions 1.

The figure below shows the set up of apparatus for the preparation of ethyl ethanoate from the reaction of etanol with ethanoic acid.

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Liebig condenser

Water bath

Mixture of ethanol ethanoic acid , and concentrated sulphuric acid

Heat

a)

On the Liebig condenser above, mark ‘X’ to indicate where water flows in and

‘Y’ where water flows out. b)

[ 1 mark]

Why is the mixture heated using a water bath ? _________________________________________________________________ _________________________________________________________________ _________________________________________________________________

[2 marks] c)

(i)

Name the reaction for the preparation of ethyl ethanoate.

___________________________________________________________ [1 mark] (ii)

Write the chemical equation for the reaction in c (i) __________________________________________________________ _ [1 mark]

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d)

The experiment is reapeated by replacing ethanol with propanol. (i) Name the ester formed . __________________________________________________________ ___ [1 mark] (ii)

State one physical property of the ester. __________________________________________________________ ___ [1 mark]

.e) ethanoic

The flow chart below shows the conversión of etanol to ethene and etanol to acid. Process I

Process II

Based on the flow chart below shows the conversión of etanol of ethene and etanol to ethanoic acid. (i)

Process I

[ 1 mark ] (ii)

Process II

[ 1 mark ] (f)

An alkane has a structural formula as shown below.

H

H Ι — C —

H ι C —

H ι C —

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H ι C —

H

Ι H

ι H

ι H

ι H

What is the name of the alkane?

[ 1 mark ] 2. Propanol reacts with acidified potassium manganate(VII) solution to produce an organic

compound X. Propanol Acidified potassium Manganate (VII) Solution

Organic Compound X Organic Compound X

a) (i) the organic compound X.

Name the reaction for changing propanol to

_______________________________________________________________ [1 mark] (ii)

Name the organic compound X. _______________________________________________________________

b)

(i)

[1 mark] Name a reagent which can be used to derive oranic compound Y when propanol and X react with one another. ______________________________________________________________

[1 mark] (ii)

Name the homologous series to which compound Y belongs to. _______________________________________________________________

[1 mark] (iii)

Draw the structural formula of compound Y.

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Figure 2.1 shows changes of a carbon compound involving a series of reactions. +H2

Propane

Alumina Alkene

Heat

Propanol Heat

Potassium dichromate(IV) in acid Propanoic acid Figure 2.1 (a) (b)

Draw the structural formulae of two propanol isomers. Name both isomers.

[ 4 marks ]

The information below is regarding alkene Y: • • • •

Carbon 85.7% Hydrogen 14.3% Relative molecular mass = 42 Relative atomic mass of H = 1 and C = 12

Based on the information of the alkene Y:

(c )

(i) (ii) (iii) (iv)

Determine the molecular formula Draw the structural formula Name the alkene Write the general formula for its homologous series [ 8 marks ]

(i)

Table 2.2 shows the results of a test to differentiate between alkene Y and propane. Procedure

Observations

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Bromine water is added to alkene Y Bromine water is added to propane

Brown colour is decolourized Brown colour remains

Table 2.2 Explain why there is difference in these observations. [ 4 marks ] (ii)

Table 2.3 shows results of latex coagulation. Procedure Propanoic acid is added to latex Latex is left under natural conditions

Observations Latex coagulates immediately Latex coagulates slowly

Table 2.3 Explain why there is a difference in these observations.

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[ 4 marks ]