1

The Uses of Sulphuric Acid in Daily life

Manufacture fertiliser

Manufacture detergents

Manufacture pesticides

Manufacture synthetic fibres

Manufacture paint pigments

As the electrolyte in lead-acid accumulators

To remove metal oxides from metal surface

SULPHURIC ACID

2

Environmental Pollution by Sulphur Dioxide

Pollution of Sulphur Dioxide

Burning of fossil fuels

Fossil fuels such as petroleum.It contain sulphur.Sulphur dioxide is produced when fossil fuels are burned

Affects the respiratory system

Sulphur is a poisonous and acidic gas.It causes coughing, chest pains, shortness of breath, lung diseases and bronchitis

Burning of sulphur in industrial area

The contact process and the burning of coals or fuels produce high sulphur dioxide content

Affect of acid rain

Sulphur dioxide gas dissolve in atmospheric water to produce sulphurous acid, H2SO3 and sulphuric acid,H2SO4. These acids causes acid rain.

Acid rains

corrodes

concrete building

and metal

structures

Acid rain increase the acidity of

soil, unsuitable for growth and

destroys the roots of plants.

Acid rain reacts with minerals in the soil to produce salts which are leashed out of the top soil; essential nutrition for plants growth are depleted (plants die of malnutrition and diseases)

Acid rain increase the acidity

of water in lake and rivers,

causes aquatic organisms die

and disturbs the ecosystem

3

The

Indu

stria

l Pro

cess

in M

anuf

actu

re o

f Sul

phur

ic A

cid

Stag

e 1

Stag

e 2

Stag

e 3

4

Stage 1• Burning of sulphur in dry air in the furnace

• Burning of metal sulphides such as zinc sulphide also produces sulphur dioxide.

• The sulphur dioxide is mixed with excess air. The mixture is then died and purified to remove impurities such as arsenic compounds.

• Arsenic compounds found in sulphur will poison the catalyst in the converter , make the catalyst ineffective

Production of sulphur dioxide gas, SO2

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

• Mixture of sulphur dioxide and excess dry oxygen is passed through a converter.

• Sulphur dioxide is oxidised to sulphur trioxide.• 98%conversion from sulphur dioxide to sulphur trioxide is

achieved under condition:i. Catalyst : vanadium (V) oxide,V2O5ii. Pressure: 1 atmosphereiii. Temperature:450°C – 550°C

Stage 2 Conversion of sulphur dioxide to sulphur trioxide, SO3

Stage 3 • In the absorber, sulphur trioxide is dissolve in concentrated sulphuric acid to produce oleum , H2S2O7 a viscous liquid.

• Oleum is then diluted with equal volume of water to produce concentrated H2SO4 (98%)

Production of sulphuric acid

Flow Chart of Contact Process

Sulphur Sulphur Dioxide, SO2

Oleum, H2S2O7

Sulphur trioxide , SO3

Sulphuric acid , H2SO4

5

AMMONIA AND ITS SALT

THE USES OF AMMONIA IN INDUSTRY

Nitric acid

Detergents

Prevent coagulation of latex

Paint and colouring

Synthetic fabric

Explosive (TNT)

Synthetic fertiliser

Cooling agent

6

The manufacture of nitrogenous fertiliser

Ammonia reacts with sulphuric acid through neutralisation to produce ammonium sulphate

Ammonium sulphate

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

Ammonia reacts with nitric acid through neutralisation to produce ammonium nitrate

NH3(aq) + HNO3(aq) NH4 NO3(aq)

Ammonium nitrate

Ammonia reacts with carbon dioxide at temperature of 200°C and pressure of 200 atmosphere to produce urea

urea

2NH3(g) + CO2(g) CO(NH2)2(s)+H2O(l)

Ostwald process • In the Ostwald process, ammonia is concerted into nitric acid by three stages

Ammonia is oxidised to nitrogen monoxide gas in the presence of platinum as catalyst

4NH3(g) +5O2(g) 4NO(g) + 6H2O(g)

Stage 1

Nitrogen monoxide is further oxidised to nitrogen dioxide

2NO(g) + O2(g) 2NO2(g)

Stage 2

Nitrogen dioxide is dissolve in water to produce nitric acid

2NO(g) + H2O(l) HNO3(aq) + HNO2(aq)

Stage 3

The properties of ammoniaVery soluble

in water

Change red litmus paper blue

Colourless and pungent gas

7

The Industrial Process in the Manufacture of Ammonia

The nitrogen and hydrogen gases are combined

The gases are compressed at 200 atmosphere, 450°C

The gases pass through the converter. Iron is used as a catalyst

The Gases are cooled down until the ammonia condenses

Ammonium fertilisers The ammonium stored as a liquid under pressure. The excess hydrogen and nitrogen gases are recycled to continue the reaction• Nitrogen is absorbed by plants in the form of

soluble nitrates, NO3- to produce protein • Ammonium fertilisers are used to replace elements

in soil used up by plants.• Ammonium ions, NH4

+ can be converted into nitrate ions by bacteria living in the soil.

• The fertiliser with higher percentage of nitrogen is more effective and this can be determined as below:

Percentage of nitrogen by weight

8

The physical properties of pure metal

Ductile • Ductile is the

ability to be stretched

Malleable• Malleable is

the ability of a metal to be shape

High melting and boiling point• The strong force of

attraction between metal atoms requires high energy to overcome it. Hence, metal have high melting points.

High density• In solid state, the atoms

in pure metal are orderly arrange and closely packed, causes pure metal to have high density

Good conductors

Alloys

Meaning and purpose of making alloys

Aim of making alloys

• Pure metal such iron and tin are easily corrode in polluted , damp or acidic air

• Alloying can prevent metals from corrosion due to the formation of oxide layer on the surface of the metal

To prevent corrosion

• Adding the little carbon to iron metal produces steel which is very hard alloy of iron

• Adding magnesium to aluminium metal produces an alloy called Magnalium

• Adding tin copper metal produces bronze. Bronze is an alloy harder than tin and copper

• Pure metal can rust and tarnish easily because of the formation of metal oxides

• Alloying can maintain the lustre on the surface of metal

To increase the strength and hardness

To improve the appearance

9

The uses of alloys

Stainless steel

Pewter Manganese steel(Hadfield steel)

Bronze

Cupro-nickel brass

Duralumin

steel

75% copper + 25% nickel• Hard-wearing• Attractive silver colour

and shiny • Does not rust

75% copper + 25% zinc• Harder than copper • Does not corrode • Shiny and strong • malleable

74% iron +18% nickel• Does not rust • Hard• Strong • Withstand corrosion better

than carbon steel

99.5% iron + 0.5% carbon• Very hard • strong

97% tin + 3% antimony and copper• Shiny and

attractive appearance

• Does not corrode• Easily cast

95% aluminium + 3% copper + 1% mangan + 1% manganese• Hard• Does not corrode• Light but strong

85% iron + 13.8% manganese + 1.2% carbon • Very hard

88% copper + 12% tin• Harder than brass• Does not corrode• Does not rust• Sonorous• Attractive appearance• Easily shaped

10

Synthetic polymers

Natural polymers

protein carbohydrates Natural rubber

• Monomer amino acide.g. in muscles, skin, silk, hairs, wool and furs

• Monomer glucosee.g. in starch and cellulose

• Monomer isoprene

(2-methylbuta-1,3-dienee.g.in latex

Synthetic polymers and their uses

Styrene-butadiene rubber(SBR)(monomers: styrene & butadiene

Neoprene (monomers : chloroprene)Butyl rubber(monomers: isoprene)

Synthetic rubber

Nylon (monomers : diamine and dicarboxylic acid)Terylene (monomers: diol and dicarboxylic acid

thermoplastic

Synthetic fibres

Polyvinyl chloride (PVC) (monomers: chlorothene)Polythene (monomer : ethene)polystyrene (monomers: phenylethene)Polypropene (monomers : propene)Prespex (monomers : methyl metacrylate)

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Issues on the use of synthetic polymer in daily life

Synthetic polymer

Strong and light

Can be made to have special properties

cheap

Easily moulded or shaped and be coloured

Able to resist corrosion

Effect of disposal of synthetic polymer

Air pollution: caused by burning of plastic• E.g. burning of PVC will produce dioxin. Dioxin

will destroy human immune system, reproductive system and nervous system

Soil pollution: • Plastic thrown on land lift up our

living spaces • Destroys the beauty of

environment• Plastic also causes the soil not

suitable for planting because plastics inhibit the growth of root

Water pollution: • Plastics will stop the flow of river

water and drains. This will cause flash floods.

• Plastics also causes the death or marine organisms if they mistaken the plastics as food

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Ways to dispose synthetic polymers in order to preserve the environment

Recycle

biodegradable

Use own plastic products reuse

replacement

convertion

• Take part in plastic recycling activities by sending recyclable products to recycle centers

• Buy recyclable or biodegradable products with little packaging

• Use biodegradable plastics which can be decomposed by microorganisms

• Reuse goods that are usually thrown away. For example, plastic containers and bags can be made into decorative item

• Bring our food container, shopping bag and basket

• Convert used products made from synthetic polymers into something useful. For example, used tyres can be converted into playground equipment.

• Use others materials to replace plastic products. For example, use paper bags instead of plastic bags

13

Glass and ceramics

Properties of glass

Impermeable to liquid

Electrical insulator

Heart insulators Chemically inert

Hard but brittle

Transparent

Properties, composition and uses of different types of glass

Name of glass Properties Example of uses

Fuse glass(99% SiO2 + 1% B2O3)

• High melting point (1700°C)• Resistant to thermal shock• High temperature and

chemical durability • Transparent to ultraviolet and

infrared light• Difficult to be made into

different shapes

• Telescope mirrors • Laboratory glass wares• Lenses• Optical fibres• Arc tubes in lamps

Soda-lime glass (70%SiO2 + 15%

Na2O + 10% CaO + 5% others)

• Low melting point( 7000°C)• Does not withstand heat • Cracks easily with sudden

temperature chances• Easy to mould and shape• Transparent to visible light• Good chemical durability• High thermal expansion

coefficient

• Bottles • Window panes• Flat glass• Light bubbles• Industrial and art objects

Borosilicate glass (80% glass SiO2 +

15% B2O3 + 3% Na2O + 1% Al2O3)

• Quite high melting point (800°C)• Does not crack easily with

sudden change in temperature • Breaks easily • More resistant to chemical attack• Does not break easily

• Laboratory apparatus • Cooking utensils• Electrical tubes• Glass pipelines

Lead glass (55% SiO2 + 30% PbO + 10%

K2O + 3% Na2O + 2% Al2O3

• Low melting point (600°C)• High refractive index• High density• Reflects light rays

• Crystals • Prism• Tableware• Art objects

14

Properties of ceramicsExtremely hard and

strong but brittleAble t withstand or resists compression

Good insulators of electric and heat

Inert to chemicals(withstand corrosion)

Has a very high melting point

The uses of improved glass and ceramics for specific purpose

Glass optical fibre

• A pure glass thread that conducts light• The fibre can transmit massage

modulated onto light waves• Used in medical instruments, local area

networks (LAN) and control board displays

• Fibre optic cables are much lighter and thinner than the metal cables.

• It can carry mode data than metal cables

Conducting glass

• A type of glass that can conduct electricity

• Produced 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

• Another type is produced embedding thin gold threads in glass to conduct electric current and produce heat

• Used in windows of aircraft

Glass - ceramic

• Rearrange its atoms into regular patterns by heating glass to form strong materials

• It can withstand high temperature, chemical attacks, better mechanical strength and better electrical insulators compared to normal glass

• Used in tiles, cookware, rockets and engine blocks

Ceramic superconductor

• Superconductors can conducts electricity at low temperature without resistance and without loss of electrical energy as heat

• Used to make light magnates, electric motors and electrical generators

Photochromic glass

• A type of glass sensitive to light intensity

• The glass darken when exposed to sunlight but becomes clear when light intensity decrease

• This is produced when dispersion of silver bromide, AgBr or silver chloride, AgCl and copper (I) chloride is added to normal glass

• Used in windows, sunglasses and instrument control

15

Appreciating various synthetic industrial

• Sources of materials are limited so we should not waste them and use them carefully

• We should minimise the use of non-biodegradable synthetic materials or make them biodegradable

• A responsible and systematic method of handling should be practiced

• The understanding of the interaction among materials enables new materials to be developed

• New materials is created to improve our daily life

Handling synthetic material and their wastes

The importance of doing research and development

• New needs and new problems will stimulate the development of new synthetic materials

• For example: New plastic composite

materials will replace metal to make a stronger and lighter car body

New superconductor made from composite materials are developed.

Justify the importance of synthetic materials in daily life

16

Composite material

Composite materials

component Properties of component

Properties of composite

Uses of composite

Reinforced concrete concrete • Hard but brittle• Low tensile

strength

• Stronger • Higher tensile

strength • Does not corrode

easily • Cheaper• Can be moulded

into any shape• Can withstand very

high apply forces • Can support very

heavy loads

• Construction of roads

• Rocket launching pads

• High-rise buildings

steel • Strong in tensile strength

• Expensive • Can corrode

Superconductor • Copper (II)oxide

• Yttrium oxide

• Barium oxide

• Insulators of electricity

• Conducts electricity without resistance when cooled by liquid nitrogen

• Magnetically levitated train

• Transformers• Electric cable• amplifier

Photochromic glass • glass • Transparent • Not sensitive to

light

• Reduce refraction of light

• Control the amount of light passes through it automatically

• Has the ability to change colour and become darker wen exposed to ultraviolet light

• Information display panels

• Light detector device

• Car windshields• Optical lens• Silver

chloride or silver bromide

• Sensitive to light

Fibre optics • Glass with low refraction index

• Transparent • Does not reflect

light rays

• Low material cost • Reflect light rays and

allow to travel along the fibre

• Can transmit electronic data or signals, voice and images in the form of light along the fine glass tubes at great speeds

• Transmit data using light wave in telecommunication

• Glass with higher refractive index

Fibre glass • glass • High density • Strong but brittle • Non-flexible

• High tensile strength • Moulded and

shaped • Inert to chemicals • Light strong• Tough• Not inflammable• Impermeable to

water• Resilient • flexible

• Car bodies• Helmets• Skies• Rackets• furniture

• Polyester plastic

• Light • Flexible• Inflammable• Elastic but weak