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8/8/2019 Complete Folio

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(H4SO4)USES OF SULPHURIC ACID

1. Sulphuric acid is used to produce chemical fertilizer such asammonium sulphate and potassium sulphate, which are highlysoluble in water and can be easily obsorbed by plant.

2. Car batteries contain sulphuric acid which is used as the electrolyte.3. Sulphuric acid also used in the making of artificial silk-like fibres

and rayon.

4. Chemical like paints, dyes and drug use sulphuric acid as one of theircomponent materials.

5. Used in school laboratories as a strong acid.

MANUFACTURE OF SULPHURIC ACID

1. Sulphuric acid is manufactured in industry though contact process2. The process contain three stages:

STAGE1:Production Of Sulphur Dioxide From Sulphuri. Combustion of sulphur or sulphide ores in the air produce sulphur

dioxide SO2.

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

ii. Sulphur dioxide is dried and purified.

STAGE2:Production Of Sulphur Trioxide From Sulphur Dioxidei. The purified sulphur dioxide SO2 and excess air are passed over

vanadium(V) oxide V2O5 at controlled optimum condition optimumcondition to produce sulphur trioxide SO3.2SO2(g)+O2(g) 2SO3(g)

ii. The optimum used area) Temperature:450-500Cb) Pressure: 2-3 atmospheresc) Catalyst: Vanadium(V) oxide

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iii. Under controlled optimum conditions, 98% conversion ispossible. Sulphur dioxide and oxygen that have not reacted areallowed to flow back again over the catalyst in the converter.

STAGE3: Conversion of trioxide to sulphuric acidi. Sulphur trioxide SO2 is dissolved in concentrated sulphuric acid H2SO4to form oleum H2S2O7 which is then diluted with water to formsulphuric acid H2SO4.

SO3(g)+H2SO4(l)H2S2O7(l) Oleum

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

ii.The two reactions in stage3 are equivalent to adding sulphur trioxidedirectly into water.

SO3(g)+H2O(l)H2SO4(aq)

iii. The addition of sulphur trioxide directly into is not carried outbecause the reaction is vary vigorous; a lot of heat is given off. As aresult, alarge cloud of sulphuric acid fumes is produced, which iscorrosive and causes severe air pollution.

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The Contact Process


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In the converter

SULPHUR DIOXIDE AND ENVIRONMENTAL POLLUTION

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Sulphur

Oxygen

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

SO2(g) +

H2SO4(aq)H2S2O7(l)H2S2O7(l) +

H2O(l)2H2SO4(aq)

2SO(g) + O2(g)2SO3(g)

Temperature: 450-500CPressure: 2-3atmospheresCatalyst: Vanadium(V)oxide

Oxygen

Unreacted2%so2 isflowed back

to convertertogether withoxygen

Outline Of Contactrocess


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1.Sulphur dioxide is one of the by-product of contact process. It is acolourless and poisonous gas with a vary pungent smell.

2. Sulphur dioxide which escape into the air causes air pollution.3. Sulphur dioxide is an acidic which dissolves in water to form

sulphurous acidic, H2SO3. In the atmosphere, sulphur dioxide dissolve

in water droplets to form sulphurous acidic.

SO2(g) + H2O(l) H2SO3(aq)

4. Oxidation of sulphur acid by oxygen produce sulphuric acid, H2SO4,which falls to the earth as acid rain. Sulphur trioxide is also easilyoxidised in the air to form sulphur trioxide. Sulphur trioxide dissolvein rainwater to produce sulphuric acid.

SO3(g) + H2O(l) H2SO4(aq)

Acid rain and environmental pollution

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(NH3)USES OF AMMONIA

1.Ammonia that is produce commercially has many uses.2.It uses:

i. In the manufacture of chemical fertilizers such asammonium sulphate, ammonia nitric, ammonia phosphate andurea.

ii. To manufacture nitric acid and explosive.iii. In the making of synthetic fibre and nylon.iv. As a degreasing agent in aqueous form to remove greasy

stains in the kitchen.v. To prevent the coagulations of latex

PROPERTIES OF AMMONIA GAS

1.The physical properties of ammonia gas include the following:i. It colourless and has a pungent odour.ii. It is vary soluble in water and form a weak alkaline solution.iii. It less dense then water.

iv. It easily liquified (at about 35.5C) when cool.2.The chemical properties of ammonia gas:a) Ammonia gas dissolves in water to form a weak alkali.

NH3(g) + H2O(l) NH4+(aq) + OH-(aq)

b)The presence of hydroxide icon causes the aqueous solution tobecome alkaline. Thus aqueous ammonia solution:i. Turns red litmus paper blue.ii. Reacts with acid to form only salt and waterin neutralizationreaction.

NH3(aq) + HCI(aq) NH4CI(aq)

2NH3 + H2SO4(aq) (NH4)2SO4(aq)

iii. Reacts with solution of metallic cations to produce precipitates.

Fe+(aq) + 2OH(aq) Fe (OH)2(s) (Form ammonia solution) Dirty green precipitate

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MANUFACTURE OF AMMONIA IN INDUSTRY

1. Ammonia is manufacture on a large scale in industry through thehaber process. In this process, ammonia is formed form directcombination of nitrogen and hydrogen gas in the volume ratio 1:3.

2. The gas nitrogen obtain form the fractional distillation of liquefied air.The hydrogen gas is obtained form the cracking of petroleum or fromthe catalysed reaction of natural gas, CH4, with steam.

CH4(g) + H2O(g) CO(g) + 3H2(g)

3.The mixture of nitrogen and hydrogen gases is passed over an ironcatalyst under controlled optimum condition as below to formammonia gas.

i. Temperature: 450-500Cii. Pressure: 200-500 atmospheresiii. Catalyst used: Iron fillings

N2(g) + 3H2(g) 2NH3(g)

4.Under these control optimum condition, only 15% of the gas mixtureturn into ammonia gas. The nitrogen and hydrogen that have notreacted are then flow back over the catalyst again in the reactorchamber.

5.The ammonia product is then cooled at a low temperature so that itcondenses into a liquid in the cooling chamber.

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The HaberProcess


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AMMONIUM FERTILIZERS

1. Nitrogen is required in large amount by plant to make proteinswhich are necessary for growth and cell repair.

2. Most plant are not able to get a nitrogen supply directly from the airalthough it is abundant in the air (78%). Plants can only absorbsoluble nitrogen compounds from soil through their roots.

3. The nitrogen compounds are usually soluble nitric salt, ammoniaand ammonia salt which are manufacture aschemical fertilizer.

4. Reactions of ammonia with acids produceammonium fertilizers.

NH3(aq) + HNO3(aq) NH4NO3(aq)Ammonium

nitrate

3NH3(aq) + H3PO4(aq) (NH4)3PO4(aq) Ammonium phosphate

2NH3(aq) +H2SO4(aq) (NH4)2SO4(aq) Ammonium

sulphate

ARRANGEMENT OF ATOMS IN MATELS

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NitrogenHydroge

n

N2 and H2 are mixed in theproportion of 1:3

N2(g) + 3H2(g) 2NH3(g)Temperature: 450-500CPressure: 200-500atmospheresCatalyst used: Iron fillings

Liquidammonia

In cooling chamber Unreacted N2and H2 gasesIn the reactor chamber

Outline Of Haberrocess


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1. The atom of pure metals are packed together closely. This causesthe metal to have a hight density

2. The forces of attraction between atoms (metallic bonds) are strong.More heat energy is needed to overcome the metallic bond so thatthe atoms are further apart during the melting. This is why metals

usually have hight melting point.3. Heat energy can be transferred easily from one atom to the next byvibration. This make metal good conduct of heat.

4. The freely moving outermost electrons within the metals structureare able to conduct electricity. Metal are, therefore, good electricalconductors.

5. Since atoms of pure metal are of the same size, they are arrangedorderly in a regular layered pattern. When a force is applied tometal, layer of atom slide easily over one another. This make puremetals soft, malleable and ductile.

WHAT ARE ALLOYS?

1. Pure metal are usually too soft for most uses. They also have a lowresistance to corrosion. They rush and tarnish easily.

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Force

Layer of atom

Metals areductile

ForceThe shape ofthe metal

Matel are


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2. To improve the physical properties of metal, a small amount ofanother 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)

THE PURPOSE OF MAKING ALLOYS:1. Increase the strength

a. Pure iron is soft and vary malleable. When a small amount ofcarbon is added to iron, an alloy, steal is formed. The morecarbon is added, the stronger the steel becomes.

b. Pure aluminium is light but not strong. With a small amount ofcopper and magnesium are added to aluminium, a strong,light and durable alloy call duralumin is produced.

2. Improving the resistance to corrosion

c.Iron rust easily but stainless steel which contains 80.6% of iron,0.4% of carbon, 18% of chromium and 1% of nickel does notrush. These properties make stainless steel suitable formaking surgical instrument and cutlery.

d. Pure copper tarnish easily. When zinc (30%) is added, theyellow alloy which is known as brass develops a high resistance tocorrosion.

3. Enhancing the appearancea. Pewter, an alloy of tin (97%), antimony and copper is not only

hard but also has a more beautiful white silvery appearance.b. When copper is mixed with nickel to form cupronickel, an

alloy that has an attractive silvery, bright appearance is formedwhich is suitable for making coins.

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WHAT ARE POLYMER

1. Molecule that consist of a large number of small identical or similarunits joined together repeatedly are called polymer.

2. The smaller molecules that make up the repeating unit in polymer arecaller 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 naturalpolymers are starch cellulose, protein and rubber.

5. Two type of polymerisation in producing synthetic polymer areadditional polymerisation.

6. Double bonds between two carbon atoms usually undergo additionpolymerisation.

Some Common Addition Polymers

Name(s) Formula Monomer Properties Uses

Polyethylenelow density(LDPE)

(CH2-CH2)n

ethyleneCH2=CH2

soft, waxy solidfilm wrap,plastic bags

Polyethylenehigh density(HDPE)

(CH2-CH2)n

ethyleneCH2=CH2

rigid,translucent solid

electricalinsulationbottles, toys

Polypropylene

(PP) differentgrades

[CH2-

CH(CH3)]n

propylene

CH2=CHCH3

atactic: soft,elastic solid

isotactic: hard,strong solid

similar toLDPE

carpet,upholstery

Poly(vinylchloride)(PVC)

(CH2-CHCl)n

vinylchlorideCH2=CHCl

strong rigidsolid

pipes, siding,flooring

Poly(vinylide (CH2- vinylidene dense, high- seat covers,

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ne chloride)(Saran A)

CCl2)nchlorideCH2=CCl2

melting solid films

Polystyrene

(PS)

[CH2-CH(C6H5)]n

styreneCH2=CHC6H

5

hard, rigid, clearsolid

soluble inorganic solvents

toys, cabinetspackaging

(foamed)

Polyacrylonitrile(PAN, Orlon,Acrilan)

(CH2-CHCN)n

acrylonitrileCH2=CHCN

high-meltingsolidsoluble inorganic solvents

rugs, blanketsclothing

Polytetrafluoroethylene(PTFE, Teflon)

(CF2-CF2)n

tetrafluoroethyleneCF2=CF2

resistant,smooth solid

non-sticksurfaceselectricalinsulation

Poly(methylmethacrylate)(PMMA, Lucite,Plexiglas)

[CH2-C(CH3)CO2CH3]n

methylmethacrylateCH2=C(CH3)CO2CH3

hard,transparentsolid

lightingcovers, signsskylights

Poly(vinylacetate)(PVAc)

(CH2-CHOCOCH

3)n

vinylacetateCH2=CHOCOCH3

soft, sticky solidlatex paints,adhesives

cis-Polyisoprenenatural rubber

[CH2-CH=C(CH3)-CH2]n

isopreneCH2=CH-C(CH3)=CH2

soft, sticky solid

requiresvulcanizationfor practicaluse

Polychloroprene (cis + trans)(Neoprene)

[CH2-CH=CCl-CH2]n

chloropreneCH2=CH-CCl=CH2

tough, rubberysolid

syntheticrubberoil resistant

Uses of synthetic polymers

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SYNTHETIC POLYMERS IN DAILY LIFE

1. Synthetic polymers have many advantages over other type ofmaterials:

a. They are cheap, light-weight and translucent.b. They are easily coloured, easily moulded and shaped.c. They are non-corrosive, waterproof and good insulator.d. They are durable and long lasting because they are resistant to

decay, rusting and chemical attacks.2. There are disadvantage using synthetic polymer:

a. Most of the synthetic polymer are flammable. When a syntheticpolymer material catches fire, poisonous fumes are producecausing air pollution.

b. Synthetic polymers are non-biodegradable. When there aredischarge, they cause litter problem and pollute theenvironment.

c. Plastic container that are left aside in an open area collectrainwater which becomes the breeding ground for mosquitoes.

d. There are limitation in recycle have to be separated out as theaddition of non-recyclable polymers in the mixture affect theproperties of the recycled polymers.

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WHAT ARE GLASS?

1. Glass is one of the most useful but inexpensive materials in the world.Many products are made from glass because of its specialsproperties.

2. Glass is:a. Transparent, hard but brittle.b. A heat and electric insulator.c. Resistant to corrosion.d. Chemical not reaction and therefore resistant to chemical attack.

e. Easy to maintain.

Type of glass Composition Properties Uses

Fused glass SiO2: 100% Transparent

High meltingpoint

Good heatinsulator

Lens

Telescopemirrors

Laboratoryapparatus

Soda-lime glass SiO2: 75%Na2O:15%

CaO: 9%Other:1%

Low meltingpoint, easilymolded intodesired shapeand size

Low resistantto chemicalattacks

Brittle

Drinking glass,bottles

Electric bulbs

Window glass

Borosilicateglass

SiO2: 78%B2O3: 12%Na2O: 5%

CaO: 3%Al2O3:2%

Resistantchemicalattack and

durable High melting

point

Good insulatorto heat

Cookingutensils

Laboratory

glassware suchas conical flaksand boiling tube

Lead crystalglass (flint glass)

SiO2: 70%Pbo/PbO2:20%

Na2O: 10%

High refractiveindex

High density

Lenses andprisms

Decorative

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Attractiveglitteringappearance

glassware andart object

Imationjewellery

CERAMICS

1. Traditional silicate ceramics are made by heating aluminosilicate claysuch as kaolin to a vary high temperature.

2. Ceramics have many special properties that make them one of themost useful materials in our everyday life. That:

a. Are hard, strong but brittleb. Have high melting point and remain stable at high temperaturec.Are heat and electric instrumentd. Are resistant to corrosion and wear

e. Are chemically not reactivef. Do not readily deform under stress

3. Ceramic play important role in our daily life. They are uses asa. Construction materials

i. Ceramic are strong and hard, uses to make roof tiles, brickscement, sinks, and toilet bowls.

ii. They are also used to make refractory bricks because highresistant to heat.

b. Decorative itemsi. To make pottery, china plates, and porcelain vases since they

do not tarnish easily and are durable.

ii. They are used to make bathroom fixture such as floor and walltiles.

c.Electrical insulatori. Ceramic are used to make electrical insulator in electrical items

such as toasters, fridges and electrical plug.

Materials Meltingpoint/ C

Density/Gcm-3

Elasticmodulus/

GPa

Hardness/mohs

Oxideceramic

Alumina,AL2O3Beryllia, BeOZirconia, ZiO

2054

25742710

3.97

3.015.68

380

370210

9

88

Non-oxideceramicsBoron 2350 2.50 280 9

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carbide,B4C3Siliconnitride, Si3,n4

2830

1900

3.16

3.17

400

310

9

9

Metals

AluminiumSteel

6601515

2.707.86

70205

35

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WHAT ARE COMPOSITE MATERIALS?

1. A composite materials (or composite) is a structure of materials thatis formed by two or more different substances such as metal, glass,ceramic and polymer.

2. Some common composite materials are:a. Reinforces concreteb. Superconductorc.Fibre opticd. Fibre glasse. Photochromic glass

REINFORCES CONCRETEa. Concrete is hard, fireproof, waterproof, comparatively cheap

and easy to maintain. It is more important constructionmaterials.

b. The reinforces is a combination of concrete and steel.

SUPERCONDUCTORa. Metal such as copper and aluminium are good conductor of

electricity, but 20% of the electric energy is lost in the formof heat during transmission.

b. Super conductor are materials that have no resistance to the

flow of electricity at a particular temperature. Hence, 100%electricity transmission is possible.

c. One of the most dramatic properties of a superconductor isits ability to levitate a magnet. Superconductor are used tobuild magnetically levitate high-speed train (at about 552km/h).

d.Superconductor are used to make chips for smaller andfaster supercomputer. Superconductor also play animportant role in high speed data processing in internetcommunication.

FIBRE OPTICa. Fibre optic is a composite material that in used to transmit

signals for lightwave.

b. Fibre optic is used in

Telecommunicate where the telephone substation are likedby fibre optic cables.

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Domestic cable television network

Closed circuit television security system.c. Fibre optic also used in medical fields. It is used in a number

of instrumentwhich enable the investigation for internal body part

without having toperform surgery

FIBRE GLASSa. Fibre glass is glass in the form of fine threads. Molten gas is

dropped onto arefractory rating disc when the glass flies off the disc glass

to form fibre.b. Fibre glass is strong than steel, do not burnt, stretch or rot,

resistant to fireand water but is brittle.

c. When fibre glass added to a plastic, a new composite

material fibre glassreinforces plastic is formed.

d. Fibre glass reinforces plastic has more superior propertiesthan glass and

plastic. It is

Extremely strong

Light weigh

Resistant to fire and water

Can be molded, shaped and twisted

PHOTOCHROMIC GLASSa. When 0.01 to 0.1% of silver chloride (a type of photochromicsubstances) and a small amount of copper (II) chloride areadded to molten silicon dioxide, photochromic glass isformed.

b.The photochromic glass has a special property. It is darkwhen exposed to strong sunlight or ultraviolet.

c. Photochromic glass is suitable for making sunglasses.

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