CHAPTER 9 :

NAME: Arivaran a/l Ravichantar CLASS: 4 Amanah SCHOOL: SMK Puchong SUBJECT : Chemistry

BIODATA

Name Class

: :

Arivaran a/l Ravichantar 4 Amanah 930228-14-5101 No. 9, Jalan Indah 2/8, Taman Puchong Indah, 47100 Puchong, Selangor Darul Ehsan.

I.C. Number : Address :

Phone No. E-mail

: :

017-6817601 r.arivaran@yahoo.com

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CONTENT

Content Biodata 9.1 Sulphuric acid 9.1.1 Properties of sulphuric acid 9.1.2 The uses of sulphuric acid 9.1.3 The industrial process in manufacture of sulphuric acid 9.1.4 Environmental pollution by sulphuric acid 9.2 Ammonia and its salt 9.2.1 Properties of ammonia 9.2.2 The uses of ammonia 9.2.3 The industrial process in manufacture of ammonia 9.3 Alloys 9.3.1 Arrangement of Atoms in Metals 9.3.2 What are Alloys 9.3.3 Composition, Properties, Uses of Alloys 9.4 Synthetic polymers 9.4.1 What are Polymer, Properties of Polymers 9.4.2 Monomers in synthetic Polymers 9.4.3 Examples of Synthetic Polymers & Their Uses 9.5 Glass and ceramics 9.5.1 Glass 9.5.2 Ceramics 9.6 Composite material Conclusion of Topic Acknowledgment References

Page 2 4 5 9 13 14 16 17 19 20 21 23 24 25 26 27 29 31 33 34 35

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9.1 SULPHURIC ACID9.1.1 Properties of sulphuric acid

1. Sulphuric acid is a strong mineral acid. 2. Its molecular formula is H2SO4. 3. It is soluble in water. 4. Sulphuric acid is a non-volatile diprotic acid. 5. It is a highly corrosive, dense and oily liquid. 6. Concentrated sulphuric acid is a viscous colourless liquid. Figure 9.1 A molecule of sulphuric acid.

Soluble in water Non-volatile acid Diprotic acid

Highly corrosive

Properties of sulphuric acid

Dense

Oily liquid

Viscous colourless liquid

Figure 9.2 Properties of sulphuric acid

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9.1.2 The uses of sulphuric acid 1) To manufacture fertilizers There are many fertilizers that can be made of sulphuric acid. Some of them are: a) Calcium dihydrogen phosphate (superphosphate) 2 H2SO4 + Ca3(PO4) 2 Ca(H2 PO4) 2 + 2CaSO4 sulphuric acid + tricalcium phosphate calcium dihydrogen phosphate

b) Ammonium sulphate H2SO4 +2NH3 (NH4) 2SO4 sulphuric acid + aqueous ammonia ammonium sulphate

c) Potassium sulphate

H2SO4 +2NH3 (NH4) 2SO4 sulphuric acid + aqueous ammonia ammonium sulphate

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2) To manufacture detergents Sulphuric acid reacts with hydrocarbon to produce sulphonic acid. Sulphonic acid is then neutralized with sodium hydroxide to produce detergents. Examples of hydrocarbon 3) To manufacture synthetic fibres Synthetic fibres are polymers ( long chain molecules). Rayon is an example of a synthetic fibre that is produced from the action of sulphuric acid on cellulose. 4) To manufacture paint pigments The white pigment in paint is usually barium sulphate, BaSO4. The neutralization of sulphuric acid and barium hydroxide produces barium sulphate. 5) As an electrolyte in lead-acid accumulators 6) To remove metal oxides from metal surfaces before electroplating 7) To manufacture pesticides 8) The uses of sulphuric acid in school laboratories are: a. b. c. d. e. As a strong acid As a drying or dehydrating agent As an oxidizing agent As a sulphonating agent As a catalyst

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Remove metal oxides from metal surfaces before electroplating

Manufacture pesticides

As an electrolyte in lead-acid accumulators

Manufacture fertilizers

Uses of sulphuric acid

Manufacture paint pigments

Manufacture detergents

Manufacture synthetic fibres

Figure 9.3 Uses of sulphuric acid

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making fertiliser 18% 1%

38%

paints

12 %

chemicals

18% 13 %

detergents

removing dust from steel

Figure 9.4 Uses of sulphuric acid in industry

other uses

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9.1.2 The industrial process in manufacture sulphuric acid 1. Sulphuric acid is manufactured by the Contact process. 2. Sulphuric acid is produced from sulfur, oxygen and water via the contact process. 3. The Contact process involves three stages.

Sulphur

Sulphur dioxide Sulphur trioxide Sulphuric acidI II III I

4. Stage I: Production of sulphur dioxide gas, SO2. This can be done by two methods, a) Burning of sulphur in dry air. S + O2 SO2 b) Burning of metal sulphide such as zinc sulphide in dry air.

2ZnS + 3O2 2SO2 + 2ZnO

5. Stage II: Conversion of sulphur dioxide to sulphur trioxide SO3. This is then oxidised to sulfur trioxide under the following conditions: a) The presence of a vanadium(V) oxide as a catalyst. b) A temperature of between 450C to 550C. c) A pressure of one atmosphere 2 SO2 + O2 2 SO3 9

6. Stage III: Production of sulphuric acid a) Sulphur trioxide is dissolved in concentrated sulphuric acid, H2SO4 to produce oleum, H2S2O7 H2SO4+ SO3 H2S2O7

b) Oleum is reacted with water to form concentrated H2SO4.

H2S2O7+ H2O 2 H2SO4

7. In stage II, sulphur dioxide is dried first before being added to dry air to produce sulphur trioxide. This is: a) b) To remove water vapour To remove contaminants

8. In stage III, sulphur trioxide is not dissolved directly in water to produce sulphuric acid. This is because: a) b) sulphur trioxide has low solubility in water sulphur trioxide reacts violently and mists are formed instead of a liquid

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\

The Contact Process

Sulphur

Oxygen In the converter

S(s) + O2(g)SO2(g) Oxygen

2SO(g) + O2(g) 2SO3(g) Temperature: 450-500C Pressure: 2-3 atmospheres Catalyst: Vanadium (V) oxide

SO2 (g) + H2SO4 (aq)H2S2O7(l) H2S2O7 (l) + H2O (l)2H2SO4(aq)

Unreacted 2%so2 is flowed back to converter together with oxygen

Outline Of Contact process

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Sulphur or metal sulphide burned in air

Sulphur dioxide, SO2 a) the presence of a vanadium(V) oxide as a catalyst. b) a temperature of between 450C to 550C. c) a pressure of one atmosphere

Sulphur trioxide, SO3 dissolved in sulphuric acid, H2SO4

Oleum, H2S2O7 diluted with equal volume of water H2O

Concentrated sulphuric acid H2SO4

Figure 9.5 Flowchart of Contact process

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9.1.3 Environmental pollution by sulphuric acid

1. 2. 3. 4. ii. iii. iv. 5. i. ii.

Sulphur dioxide is the main byproduct produced when sulfur-containing fuels such as coal or oil are burned. Sulphuric acid is formed by atmospheric oxidation of sulphur dioxide in the presence of water. It also produces sulphurous acid. Sulphuric acid and sulphurous acid are constituents of acid rain. Acid rain can cause many effects such as: i. Corrodes concrete buildings and metal structure Destroys trees and plants Decrease the pH of th soil and make it become acidic Acid rain flows into the rivers and increases the acidity of water and kill aquatic living things. Hence, we must reduce the sulphur dioxide from the atmosphere by: Use low sulphur fuels to reduce the emission of sulphur dioxide in exhaust gases Remove sulphur dioxide from waste air by treating it with calcium carbonated before it is released

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9.2 AMMONIA AND ITS SALT9.2.1 Properties of ammonia 1. A colorless, pungent gas. 2. Its molecular formula is NH3 3. It is extremely soluble in water. 4. It is a weak alkali. 5. It is about one half as dense as air 6. It reacts with hydrogen chloride gas to produce white fumes of ammonium chloride. NH3 + HCl NH4Cl 7. Ammonia is alkaline in property and reacts with dilute acids in neutralization to produce salts. For examples: NH3 + HNO 3 NH4NO 3 Figure 9.6 A molecule of ammonia.

2NH3 + H2SO4 (NH4) 2SO4

8. Aqueous solutions of ammonia produces OH and Ca2+

ions (except Na ion, K ion,

+

+

ion) forming metal hydroxides precipitate.

Fe

3+

+ 3OH Fe(OH) 3Brown precipitate

Mg

2+

+ 2OH Mg(OH) 2White precipitate

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9. Some metal hydroxides such as zinc hydroxide and copper (II) hydroxide dissolves in excess aqueous ammonia to form complexes.

Zn(OH)2 + 4NH3 [Zn(NH3)4] + 2OH Cu(OH)2 + 4NH3 [Cu(NH3)4]2+

2+

+ 2OH

Weak alkali

Extremely soluble in water

Properties of ammonia

Colorless

Pungent smell

Figure 9.7 Properties of ammonia

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USES OF AMMONIA IN INDUSTRY:To manufactu re nitrogenou s fertilisers

Examples are ammonium sulphate, ammonium nitrate and urea. The first two are prepare through neuralisation but urea is produced by the reaction of ammonia with carbon dioxide. The reaction involved are as the following: a) 2NH3 (g) + H2SO4 (aq) (NH4)2SO4 (s) ammonium sulphate b) NH3 (g) + HNO3 (aq) NH4NO3 (aq) ammonium nitrate c) 2NH3 (g) + CO2 (g) (NH2)2CO (s) + H2O (l) urea Having a low melting point, liquefied ammonia makes a good cooling agent in refrigerators and air

As a cooling agent

To prevent the coagulation of latex in the rubber industry

It neutralizes the organic acids formed by microorganisms in latex, thereby preventing coagulation and preserving the latex in liquid form.

Ammonia is converted to nitric acid in the Ostwald process:1) ammonia is first oxidised to nitrogen monoxide, NO, by oxygen in the presence of platinum as catalyst at 900C.To manufacture nitric acid in industryPt/900 6H O (l) 4NH3 (g) + 5O2 (g) 4NO (aq) + 2 2) nitrogen monoxide is further oxidised to nitrogen dioxide. 2NO (g) + O2 (g) 2NO2 (g) 3) Nitrogen dioxide and oxygen are dissolved in water to produced nitric acid. 4NO2 (g) + O2 (g) + H2O (l) 4HNO3 (aq) C

To

manufact ure explosive

a) Nitric acid is manufactured from ammonia before being used to make explosive like trinitrotoluene (TNT). b) Nitric acid, in this case, is reacted with organic substances like toluene.

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9.2.3 The industrial process in manufacture of ammonia 1. Haber process is the industrial method of producing ammonia. 2. It needs direct combination of nitrogen and hydrogen under high pressure in the presence of a catalyst, often iron. 3. Nitrogen gas used in Haber process is obtained from the frictional distillation of liquid air. 4. Hydrogen gas used in Haber process can be obtained by two methods: a) The reaction between steam and heated coke (carbon) C + H2O CO + H2

b) The reaction between steam and natural gas ( consisting mainly of methane)

CH4 + 2H2O CO2 + 5. In the Haber process: a) A mixture consisting of one volume of nitrogen gas and three volume of hydrogen gas is compressed to a pressure between 200 500 atmospheres. b) The gas mixture is passed through a catalyst of powdered iron at a temperature of 450 - 550C. c) At this optimum temperature and pressure, ammonia gas is produced. N2+ 3H2 2NH3

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The Haber process

Nitrogen

Hydrogen

N2 and H2 are mixed in the proportion of 1:3 In the reactor chamber N2(g) + 3H2(g) 2NH3(g) Temperature: 450-500C Pressure: 200-500 atmospheres Catalyst used: Iron fillings Unreacted N2 and H2 gases

In cooling chamber Liquid ammonia

Outline of Haber process

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9.3 ALLOYS9.3.1 ARRANGEMENT OF ATOMS IN METALS 1. 2. 3. 4. 5. The atom of pure metals are packed together closely. This causes the metal to have a hight density The forces of attraction between atoms (metallic bonds) are strong. More heat energy is needed to overcome the metallic bond so that the atoms are further apart during the melting. This is why metals usually have hight melting point. Heat energy can be transferred easily from one atom to the next by vibration. This make metal good conduct of heat. The freely moving outermost electrons within the metals structure are able to conduct electricity. Metal are, therefore, good electrical conductors. Since atoms of pure metal are of the same size, they are arranged orderly in a regular layered pattern. When a force is applied to metal, layer of atom slide easily over one another. This make pure metals soft, malleable and ductile.

Layer of atom slide

Force

Metals are ductile

Force

The shape of the metal change

Matel are malleable

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9.3.2 WHAT ARE ALLOYS 1. Pure metal are usually too soft for most uses. They also have a low resistance to corrosion. They rush and tarnish easily. 2. To improve the physical properties of metal, a small amount of another element (usually metal) is added to form another an alloy. 3. An alloy is a mixture of two or more metals (something non-metal) in a specific proportion. For example: a. Bronze (90% of copper and 10% of tin) b. Steel (99% of iron and 1% of carbon) 4. The purposes of making alloys include the following: a) Increase the strength i. Pure iron is soft and vary malleable. When a small amount of carbon is added to iron, an alloy, steal is formed. The more carbon is added, the stronger the steel becomes. ii. Pure aluminium is light but not strong. With a small amount of copper and magnesium are added to aluminium, a strong, light and durable alloy call duralumin is produced. b) Improving the resistance to corrosion i. Iron rust easily but stainless steel which contains 80.6% of iron, 0.4% of carbon, 18% of chromium and 1% of nickel does not rush. These properties make stainless steel suitable for making surgical instrument and cutlery. ii. Pure copper tarnish easily. When zinc (30%) is added, the yellow alloy which is known as brass develops a high resistance to corrosion. c) Enhancing the appearance i. Pewter, an alloy of tin (97%), antimony and copper is not only hard but also has a more beautiful white silvery appearance. ii. When copper is mixed with nickel to form cupronickel, an alloy that has an attractive silvery, bright appearance is formed which is suitable for making coins.

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9.3.3 Composition, Properties, Uses of Alloy

AlloyCupronic Duralumi Steel Stainless steel bronze Brass Solder Pewter Magnaliu u

Compositi onCu 75%Ni 25% Al 95% Cu 4% Mg 1% Fe 99% C Fe 73% Cr 18% Ni Cu 90% Sn 10% Cu 70% Zn 30% Pb 50% Sn 50% Sn 91% Sb 7% Cu Al 70% Mg 30%

Propertie Hard, strong, sresist corrosion Light, strong Hard, strong, cheap Hard, rust resistan t Hard, strong, shining Harder and cheaper than Cu melting Low point, strong Malleable, ductile, rust resistant Light, strong

Coins

Use s

Aeroplane part, electric cables racing bicycles Vehicles, bridges, Kitchen appliance, watches, knifes, fork, spoons, machine parts Decorative items, medals, artwork, pots & pans Musical instrument, bell, nails, screw, and pots Welding, soldering work Decorative items,souvenirs Tyre rim of racing car, skeletal body of aeroplane

The formation of alloy 21

Examples Of Alloys

Bras s

Bronze

Stainle ss Stee l

Bronze

EXAMPL E OF ALLOY

Steel

Manganes e Stee l

PewterMangane se steel

Stainless steel

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9.4 SYNTHETIC POLYMERS9.4.1 WHAT ARE POLYMER 1. Molecule that consist of a large number of small identical or similar units joined together repeatedly are called polymer. 2. The smaller molecules that make up the repeating unit in polymer are caller monomer. 3. The process of joining together a large number of monomers to form a long chain polymer is called polymerisation. 4. Polymer can be naturally occurring or man-made (synthetic). Natural polymer are found in plant and in animals for example of natural polymers are starch cellulose, protein and rubber. 5. Two type of polymerisation in producing synthetic polymer are additional polymerisation. 6. Double bonds between two carbon atoms usually undergo addition polymerisation.large molicule that is in the form of long chain with high RMM

two types:- natural polymer synteti c polyme r

Properti es of Polymer s

made up of many monomers which join together through process called polymerisatio n

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9.4.2 Monomers and repeat units The identity of the monomer residues (repeat units) comprising a polymer is its first and most important attribute. Polymer nomenclature is generally based upon the type of monomer residues comprising the polymer. Polymers that contain only a single type of repeat unit are known as homopolymers, while polymers containing a mixture of repeat units are known as copolymers. Poly(styrene), for example, is composed only of styrene monomer residues, and is therefore classified as a homopolymer. Ethylene-vinyl acetate, on the other hand, contains more than one variety of repeat unit and is thus a copolymer. Some biological polymers are composed of a variety of different but structurally related monomer residues; for example, polynucleotides such as DNA are composed of a variety of nucleotidesubunits. A polymer molecule containing ionizable subunits is known as a polyelectrolyte or ionomer

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Some Common Addition Polymers Name(s) Polyethylene low density (LDPE) Polyethylene high density (HDPE) Polypropylene (PP) different grades Poly(vinyl chloride) (PVC) Poly(vinylidene chloride) (Saran A) Polystyrene (PS) Polyacrylonitrile (PAN, Orlon, Acrilan) Polytetrafluoroet hylene (PTFE, Teflon) Poly(methyl methacrylate) (PMMA, Lucite, Plexiglas) Poly(vinyl acetate) (PVAc) Formula (CH2CH2)n Monomer ethylene CH2=CH2 Properties soft, waxy solid Uses film wrap, plastic bags electrical insulation bottles, toys similar to LDPE carpet, upholstery pipes, siding, strong rigid solid flooring

(CH2CH2)n [CH2CH(CH3)]n

ethylene CH2=CH2 propylene CH2=CHCH3

rigid, translucent solid atactic: soft, elastic solid isotactic: hard, strong solid

(CH2CHCl)n

vinyl chloride CH2=CHCl

(CH2CCl2)n

vinylidene chloride CH2=CCl2

dense, highmelting solid hard, rigid, clear solid soluble in organic solvents

seat covers, films toys, cabinets packaging (foamed)

[CH2styrene CH(C6H5)]n CH2=CHC6H5 (CH2CHCN)n (CF2CF2)n [CH2C(CH3)CO2 CH3]n (CH2acrylonitrile CH2=CHCN tetrafluoroethy lene CF2=CF2

high-melting solid rugs, blankets soluble in organic clothing solvents resistant, smooth solid non-stick surfaces electrical insulation lighting covers, signs skylights

methyl hard, transparent methacrylate CH2=C(CH3)C solid O2CH3 vinyl acetate soft, sticky solid

CHOCOCH3 CH2=CHOCO )n CH3

latex paints, adhesives

Uses of synthetic polymer

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9.5 GLASS AND CERAMICS1. The main component of both glass and ceramic is silica or silicon dioxide, SiO2. 2. Both glass and ceramic have the same properties as follow a) Hard and brittle b) Inert to chemical reactions c) Insulators or poor conductors of heat and electricity d) Withstand compression but not stretching e) Can be easily cleaned f) Low cost of production 3. Differences between glass and cerement are, glass is transparent, while ceramic is opaque. Ceramic can withstand a higher temperature than normal glass. 4. Types of glass are a) Fused glass

It is consist mainly of silica or silicon dioxide It has high heat resistance It cannot withstand high temperatures It can withstand high temperature High refractive index

b) Soda lime glass

c) Borosilicate glass

d) Lead glass

5. Uses of improved glass for specific purpose a) Photochromic glass

It is sensitive to light intensity It conducts electricity

b) Conducting glass

6. Ceramic is a manufactured substances made from clay, with the main constituent of aluminosilicate with small quantity of sand and feldspar. 7. Superconductor is one improved ceramics for specific purposes.

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GLASSGlass: The major component of glass is silica or silicon dioxide, SiO2 which found in sand.

Impermeab le to liquid

Transpare nt

Electric al insulat or

Properti es of glass

hard but brittle

Hea t insulat or

Chemica lly inert

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TYPES, COMPOSITION, PROPERTIES, AND USES OF GLASSGLASS COMPOSITION SiO2 70% Na2O 15% CaO 10% Others 4% Lead glass (crystal) SiO2 70% Na2O 20% PbO 10% Fused silicate glass SiO2 99% B2O3 1% PROPERTIES Low melting point Mouldable into shapes Cheap Breakable Can withstand high heat High density and refractive index Glittering surface Soft Low melting point (600C) Resistant to high heat &chemical reaction Does not break easily Allow infra-red rays but no ultra-violet rays High melting point (1700C) Expensive Allow ultraviolet to pass through Difficult to melt or mould into shape USES Glass container Glass panes Mirror Lamps and bulbs Plates and bowls Bottles Containers for drinks and food Decorative glass Crystal glassware Lens for spectacles Glass apparatus in lab Cooking utensils

Soda lime glass

Borosilicate glass (Pyrex)

SiO2 80% B2O3 13% Na2O 4% Al2O3 2%

Scientific apparatus like lens on spectrometer Optical lens Lab apparatus

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CERAMICSCeramics: Ceramic is manufactured substances made from clay that is dried, and heated in a kiln at a very high temperature The main component of clay is aluminosilicate (aluminum oxide and silicon dioxide) with small quantities of sand and feldspar. Unlike glass, ceramic cannot be recycled. Kaolinite is a high quality white clay that contains hydrated aluminosilicate, Al2O32SiO22H2O.

extreme ly hard & strong but brittle able to withstan d and resist corrosio n has a very high melting point

Properti es of ceramic s

good insulator of electricit y and heat

inert to chemica ls

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THE DIFFERENT CLASES OF CERAMICGROUP Mineral Cement material Oxide of ceramic Non-oxides of ceramic COMPOSITION Quartz SiO2 Calcite CaCO3 Mixture of CaSiO3 and ammonium silicate Aluminium oxide Al2O3 Silicon dioxide SiO2 Magnesium oxide MgO Silicon nitride Si3N4 Silicon carbide SiC Boron nitride BN Boron carbide B4C3

THE USES OF IMPROVED GLASS AND CERAMICS FOR SPECIFIC PURPOSES

GLASS OPTICAL FIBREA pure silica glass thread that conducts light. this fibres can transmit messages modulated onto light waves. used inmedical instrument, LAN

CONDUCTI NG GLASSa type of glass that can conduct electricity. produce by embedding a thin layer of conducting material in glass. adding a layer of indium tin(iv) oxide (ITO) acts as an electrical conductor. used in the making of LCD

GLASSCERAMICRearrange its atoms into regular patterns by heating glass to form strong material it can withstand high temperature, chemical attacks used in tile, cookware, rockets, engine blocks

CERAMIC SUPERCONUCT ORsuperconductor can conduct electricity at low temoerature without resistance, loss of electrical energy as heat used to make light magnet, electric motors, electrical generators

PHOTOCHRO MIC GLASSsensitive to light intensity the glass darken when exposed to sunlight but became clear when light intensity decresase. used in windows, sunglasses ad instrument control

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9.6 COMPOSITE MATERIAL9.6.1 WHAT ARE COMPOSITE MATERIALS 1. A composite materials (or composite) is a structure of materials that is formed by two or more different substances such as metal, glass, ceramic and polymer. 2. Some common composite materials are: a. Reinforces concrete b. Superconductor c. Fibre optic d. Fibre glass e. Photochromic glass

in the medical field: to replace organs in the form of plastic composite organ

car part now use composite material instead iron and steel. this increase the speed of the car and fuel saver

Uses of composi te material

sronger buildings are built by using reinforce concrete

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COMPOSI TE MATERIA L

COMPONENT PROPERTIE S OF COMPONE NT concrete hard but brittle low tensile strengh

PROPERTIE S OF COMPOSITE stronger higher tensile strength does not corrode easily cheaper can be moulded into shape can withstand very high applied force can support very heavy load

USE S construction of road rocket launching pads high-rise buildings

Reinforced concrete

steel

strong in tensile strength expensive can corrode Insulator of electricit y

Supercondu ctor

Cooper(ll) oxide Yttrium oxide Barium oxide Glass

Conducts electricity without resistance when cooled by liquid nitrogen

Magnetically levitated train Transformer Electric cable Computer parts

Transparent Not sensitive to light

Reduce refraction of light Control the amount of light passed through it auto. Sensitive to light

Information display panels Light detector device Car windshields Optical lens Has the ability to change colour and become darker when exposed to ultraviolet light Low material cost Reflect light rays and allow to travel along the fibre Can transmit electronic data or signal, voice and image

Photochromic glass

Silver chloride or silver bromide

Glass with low refraction index Fibre optics Glass with higher refractive index

Transparent Does not reflect light rays

Transmit glass high density strong but brittle non-flexible

data using light waves in high tensile strength moulded and shaped inert to chemicals light, strong, tough non-flammable impermeable to water resilient flexible

telecommunicati ons

car bodies helmets skies rackets

Fibre glass

polyester plasti c

light flexible inflammable elastic but weak

furniture

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CONCLUSION OF TOPICWe must appreciate these various synthetic industrial materials. One of the way is by doing continuous research and development ( R & D ) to produce better materials used to improve our standard of living. As we live in a changing world, our society is getting more complex. New materials are required to overcome new challenges and problems we face in our daily lives. Synthetic material are developed constantly due to the limitation and shortage of natural materials. New technological developments are used by scientists to make new discoveries. New materials for clothing, shelter, tools and communication to improve our daily life are developed continuously for the well-being of mankind. New needs and new problem will stimulate the development of new synthetic materials. For example, the new use of plastic composite material will replace metal in the making of a stronger and lighter car body. This will save fuel and improve speed. Plastic composite materials may one day used to make organs for organ transplant in human bodies. This will become necessity with the shortage of human organ donors. The understanding of the interaction between different chemicals is important for both the development of new synthetic materials and the disposal of such synthetic materials as waste. A responsible and systemic method of handling the waste of synthetic materials and their by-product is important to prevent environmental pollution. The recycling and development of environmental friendly synthetic material should be enforced.

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AcknowledgmentFirst of all, I wish to express my sincere thanks to GOD for his care and generosity throughout of my life.

I would like to express my sincere appreciation and my deep gratitude to Puan Ng Pek Lan, Form 4 Amanah Chemistry Teacher, SMK Puchong Batu 14 who assigned the work, and kindly supplied me with all necessary facilities for its success and helped me to complete this work.

First and foremost, I would like to express my sincere thanks to all my family members especially my parents who gave me not only financial support but also moral support and motivation to fine the solutions to all the questions given.

I am also deeply indebted to my school mates Mathiarasi a/p Bernabas, Sivaselvan a/l Subramaniam, Uberesh a/l Machap, Kavitha a/p Kasturi, Logeswary a/p Painaidu of SMK Puchong Batu 14 for their great support throughout the whole work.

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REFERENCES1. Tan Yin Toon, Loh Wai Leng, Tan On Tin, 2008, SUCCESS Chemistry SPM, Oxford Fajar Sdn.Bhd. 2. Website http://www.answers.com 3. Website http://www.wikipedia.com 4. Eng Nguan Hong, Lim Eng Wah, Lim Yean Ching, 2009, FOCUS ACE SPM, Penerbitan Pelangi Sdn.Bhd.

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