Chemistry Folio

CHEMISTRY FOLIO (FORM 4)

Name: Muhammad Farhan B. Abu Bakar

Class: 403

College Number: 11547

School: MJSC GEMENCHEH,Negeri Sembilan

Title: Manufactured Substances In industry

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MANUFACTURED SUBSTANCES IN FOOD INDUSTRY

A.Sulphuric Acid

Uses of sulphuric acid

Sulphuric acid is used in manufacturing of almost all product such as manufacture of

detergents,production of fertiliser, manufacture of aritifical fabric and many more.It’s also

used in removal of sulphur compound in crude oil and also to produce other chemical.

Manufacture of Sulphuric Acid

You can’t find sulphuric acid naturally.Sulphuric acid is the most produced chemical

as compared to other chemical.It is manufactured by a process called Contact

Process.The raw materials that been used to produce sulphuric acid is sulphur,water

and air.It has to go through 3 stages to obtain the chemical.

Stage 1

In the furnace,molten sulphur is burnt in dry air to produce sulphur dioxide,SO4.

The gas produced is purified and cooled.

S(1)+O2(g) SO2(g)

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Stage 2

In the coverter sulphur dioxide,SO2 and excess oxygen gas,O2 are passed over a few

plates of vanadium(V) oxide,V205 catalyst at 450 degree celcius to produce sulphur

trioxide,SO3

2SO2(g)+O2(g) 2SO3(g)

2SO2(g)+O2(g) 2SO3(g)

Stage 3

In the absorber,the sulphur trioxide, SO3 is first react with concentrated sulphuric

acid,H2SO4 to form a product called oleum,H2S207.

SO3(g) + H2SO4(1) H2S2O7(1)

The oleum,H2SO7 is then dilute with water to produce concentrated sulphuric

acid,H2SO4 in large quantity.This two reaction in stage three is equivalent to adding

sulphur trioxide,SO3 directly to water

H2S2O7(1) + H20(1) 2H2SO4(1)

Please refer to next page for more information.

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Sulphur dioxide and environmental pollution

Sulphur dioxide,SO2 can cause environmental problem.Almost all sulphur

dioxide,SO2 from fossil burning containing sulphur.Inhaling it will make you experience

chest pain,shortness of breath,bronchitis and lung deseases.Other than that,it can cause acid

rain.Acid rain occurs when pH of th rain is between 2.4 and 5.0.This is due to the reaction

sulphur dioxide with rainwater.

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B. Ammonia and Its Salts

Ammonia,NH3 has many uses other uses apart from manufacturing fertilisers. Most

of ammonia is converted to nitic acid,HNO3.This acid is needed to produce synthetic fibres,

explosives, wood pulp, paints, varnishes, lacquers and rocket propellants.

The properties of ammonia

Ammonia, NH3

- Alkaline- Colourless gas- Has a pungent smell- Less dense than air- Burns in oxygen gas, 02 but don’t burn in the air- Soluble in water- Gives white fume when reacted with hydrogen chloride gas,HCl

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Manufacture of ammonia

Ammonia, NH3 is manufactured through the Haber Process. This process combines

the air with hydrogen gas,H2 to form ammonia,NH3.

The ratio of one volume of nitrogen gas,N2 to three volumes of hydrogen gas,H2 is

passed through the reactor. The mixture is compressed to a high pressure of 200 atmosphere

at temperature of about 450 C. It is passed through the layers of iron catalysts to speed up the

rate of reaction.

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

The unreacted nitrogen gas , N2 and hydrogen gas, H2 are cycled back into reactor

together with the new source of nitrogen gas, N2 and hydrogen gas.

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Preparation of ammonium fertilisers

Ammonium fertilisers are one of the chemical fertilisers added to soil to replace the

elements used up by plants. The major plant nutrients include nitrogen, phosphorus, and

calcium. Ammonium fertilisers can be prepared from the reaction between ammonia, NH3

and an acid.

Some of the ammonium fertilisers in the marketing

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Sulphuric Acid

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Alloys

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Ammonia and its salt

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C.Alloys

Pure aluminium is not enough strong to withstand the great stress put on the wing of

an aeroplane when it’s flying.How can we combine the low density of aluminium with the

strength needed to make the body of an aeroplane? Alloys is the solution.

Alloy is needed in manufacture of airplanes

Arrangement of atom in metals.

Pure metals are made up of the same type of atoms and are the same sizes. The

arrangement of the atoms in metal gives their ductile and malleable properties. The orderly

arrangement of atoms in metal enables the layers of atom to slide on one another when force

is applied. Thus metals can be stretched or ductile

There are some imperfections in orderly arrangement of atoms in metals that allow

some empty spaces in between the atoms. When a metal is knocked, atoms slide. This is why

metals are malleable or can be shaped.

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What are alloys?

Two soft metals can be mixed together to make a stronger metals are called alloy.An

alloy is a mixture of two or more elements with a certain fixed composition in which the

major components is a metal. The aim of making alloys is to make them harder,stonger,more

durable and resistant to corrosion.

The uses of each different alloy depend on the properties of the alloy. For example,

cutlery is made up of stainless steel and shiny and does not rust. Table below shows the

composition and some uses of some alloys.

Alloys Composition Properties UsesBronze *90% copper

*10% tin*Hard and strong*Does not corrodes easily*Has shiny surfaces

*In the building of statue or monuments*In the making of medals, swords and artistic materials

Brass *70% copper*30% zinc

*Harder than copper *In the making of musical instruments and kitchenware

Steel *99% iron*1% carbon

*Hard and strong *In the construction of building and bridges*In the building of the body of cars and railway tracks

Stainlesssteel

*75% iron*8% carbon*18% chromium

*Shiny*Strong*Does not rust

*In the making of cutlery*In the making of surgical instruments

Duralumin *93% aluminium*3% copper*3% magnesium*1% manganese

*Light *Strong

*In the building of the body of aeroplanes and bullet trains

Pewter *96% tin*3% copper*1% antimony

*Lustre*Shiny*Strong

*In the making of souvenirs

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THE ARRANGEMENT OF ATOMS IN ALLOYS

Alloys are stronger than its pure metal. To understand this, study the atoms arranged in

alloys.

The formation of alloys

There are the different in the arrangement of atoms in an alloy when two atoms of metal

are mixed together. The present of atoms of other metals that are of different sizes disturb the

orderly arrangement of atoms in the metal. This reduces the layers of atoms from sliding.

Thus, an alloy is stronger and harder than its pure metal.

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PURE METAL A PURE METAL B

SYNTHETIC POLYMERS

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Plastics are polymers.

What are polymers?

Polymers are large molecules made up of many identical repeating sub – unit called

monomers which are joined together by covalent bonds. Monomers are joined into chain by a

process of repeated linking called polymerisation.

Some polymers occur naturally. Starch, milk, wool, protein and so on are some

example of naturally occurring polymers. On the other hand, synthetic polymers are man

- made polymers. The monomers are usually obtained from petroleum after going through the

refining and cracking process.

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Monomers in synthetic polymers

Synthetic polymers Monomer UsesPolythene Ethene Plactic begs, shopping begs,

plastic containers and insulation for electrical wiring

Polypropene Propene Piping, bottle crates, carpets, car batteries and ropes

Polyvinyl chloride, PVC

Chloroethene Artifical leather, water pipes and records

Perspex Methylmethacrylate Safety glass, reflectors, traffic signs and lens

Terylene Hexane-1, 6-diolBenzene-1, 4-dicarboxylic acid

Clothing, sail and ropes

Nylon Hexane-1, 6-diamineHexane-1, 6-dioic acid

Ropes, clothing ang carpets

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SHOULD WE CONTINUE USING SYNTHETIC POLYMERS?

Synthetic polymers are widely used today. One of the great advantages of synthetic polymers is they can de made to have special properties required for their uses. They are relatively cheap, easy to be moulded or shaped and can also be coloured.

Synthetic polymers are very stable and do not corrode or decay. However, this is also means that they are difficult to dispose. They are not easily biodegreable. Hence, they may cause pollution, blockage of drainage system and flash floods. When they are burnt, they give out harmful and poisonous gases which have a pungent smell.

Although synthetic polymers pose environmental problems, we can still continue using them but in a wiser manner. We should reduce, reuse, and recycle synthetic polymers as much as possible. The use of biodegreable polymers should be encouraged. We should also find alternatives to synthetic polymers.

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Glass and Ceramics

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Glass and made of from sand. Evidence have shown that glass has been used for more than

3000 years.Ceramics are made up from clay. Pieces of broken ceramics that are more than

6000 years old have been found.

Ceramics and glasss in our daily life

Glass

The major component of glass is silica,SiO2. Fused glass is the simplest glass.It is mainly

silica,SiO2. Fused glass is highly heat- resistant glass. You can heat it extremely and plunge

it into icy,cold water without having it cracked.

The most common glass found in the house is soda- lime glass. Mainly made up from heated

sand with limestone,CaCO3. It can be easily shaped and has a good chemical durability. It

also has a high thermal expansion. However, it can’t withstand extremely hot condition.

When a boron oxide is added to soda lime glass,borosilicate glass is formed.

Borosilicate glass has a lower thermal expetion coeficent it is also more resistant to chemical

compared to sodalime glass because it contain less alkali.It used in glass pipeline and

application which require superior resistance to thrmal shock and greater chemical durability.

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Lead crystal glass is normally called crystal or lead glass.It is mede by substituting

lead oxide for calcium and open for part of the silica used in soda lime glass.It is soft and

easy to melt.Leaad glass is used for the finest tableware or art object.

Item made up of borosilicate glass

Item made up of soda- lime glass

Item made up of lead crystal glass

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