Chemistry Form Four

Chapter 9 : Manufactured Substances in

Industry
01-Jul-2010

Nur Safina Izwani Binti Rumli

4 Ibnu Sina

Teacher Salahiah Binti Daman

TABLE OF CONTENT
 OBJECTIVES
 Understand the manufacture of sulphuric acid.
 Synthesised the manufacture of ammonia and
its salts.
 Understand alloys.
 Evaluate the uses of synthetic polymer.
 Apply the uses of glass and ceramics.
 Evaluate the uses of composite materials.
 Appreciate various synthetic industrial
materials.
ACKNOWLEDGEM
ENTS
Assalamualaikum w.b.t

I am so grateful to Allah s.w.t for giving me good health and

opportunity to finish this task by its dateline. Here, I want to thank
everyone and everybody that had helped me through the process
of finishing this task. Thank you very much and a lot of
appreciation to my parents for moral support and money, to my
Chemistry teacher for the guidelines, and to my fellow friends
who always help me in every hard situation. May ALLAH bless all
of you. I will never forget those help.

THANK YOU 
 Method Used
 Internet research

- I had did some research based on the topics given. I had

found many informations about this topic from the internet.

 Reading

- I had read my revision book of Chemistry and collect

informations from it.
 SULPHURIC ACID

Uses of Sulphuric Acid

• Fertilisers

i. Phosphate fertilizers

ii. Nitrogen fertilizers

iii. Mixed fertilizers

• Paints and pigments

• Detergents

• Fibres

i. Rayon

ii. Paper

• Metallurgy

i. Cleaning metals

• Dyes

• Other uses

i. Explosives

ii. Electrolytes

iii. Insecticides

iv. Pharmaceuticals

v. Oil refining

Manufacture of Sulphuric Acid

 The manufacture of sulphuric acid is carried out using the Contact Process
  There are three essential stages in the manufacture of sulphuric acid ;

i. Combustion of sulphur

ii. Conversion of sulphur dioxide to sulphur trioxide

iii. Formation of sulphuric acid

Contact Process

Stage 1 ; Formation of Sulphur Dioxide

1) Sulphur is burnt in air to produce sulphur dioxide.

S(s) + O2(g)  SO2(g)

2) Sulphur dioxide is also produced by roasting sulphide ores ( e.g lead

sulphide ) in air.

2PbS(s) + 3O2(g)  2PbO(s) + 2SO2(g)

3) Sulphur dioxide is then mixed with excess air.

4) The mixture is purified and died.

5) Dust and impurities such as arsenic compounds are removed to prevent the
poisoning of the catalyst.

Stage 2 ; Formation of Sulphur Trioxide

1) Sulphur dioxide is oxidized to sulphur trioxide via a reversible and exothermic

reaction.
 2) Optimum conditions used are as follows ;

 Temperature ; 450oc

 Pressure ; 1 atmosphere

 Catalyst ; Vanadium (v) oxide

3) About 97% conversion occurs under these conditions

Stage 3 ; Formation of Sulphuric Acid

1) Sulphur trioxide is dissolved in concentrated sulphuric acid to form oleum

2) Sulphur trioxide is not dissolved in water as the heat evolved vapourises the
sulphuric acid. The vapour condenses to form a mist of sulphuric acid which is
hard to collect.

3) The oleum is then diluted with water to produce concentrated sulphuric acid,
98% H2SO4

AMMONIA AND ITS SALTS

Uses of Ammonia in Daily Life

 The most important use of ammonia is as a fertilizer. Pure liquid ammonia

provides the highest concentration of nitrogen. It can be added to the soil to
help the healthy growth of plants.

 Ammonia is used in the manufacture of other nitrogenous fertilizers. These

fertilizers are mostly soluble ammonium salts obtained when ammonia is
neutralized by the appropriate acids. As example are ammonium sulphate,
ammonium nitrate, ammonium phosphate and urea.

 Ammonia is a feedstock for the manufacture of nitric acid via Ostwald

Process.

 Ammonium chloride is produced from the reaction between ammonia and

hydrochloric acid. This compound is used in the manufacture of dry cell
batteries.

 Ammonia gas has a high heat capacity and is highly compressible. These
properties make it suitable to be used as a refrigerant.
  Aqueous ammonia is found in many household cleaning products to remove
grease and oily stains.

 Ammonia is also used to make nylon and explosives.

Manufacture of Ammonia

 Ammonia is produced industrially by a process called the Haber-Bosch

Process.

 Ammonia is formed from the direct combination of nitrogen and hydrogen.

Haber-Bosch Process

1 : Nitrogen gas is obtained from the fractional distillation of liquid air.

2 : Hydrogen gas is obtained from natural gas. The methane in natural gas
reacts with steam according to the following equations.

CH4(g) + 2H2O(g)  CO2(g) + 4H2(g)

CH4(g) + H2O(g)  CO(g) + 3H2(g)

CO(g) + H2O(g)  CO2(g) + H2(g)

3 : Nitrogen and hydrogen are mixed according to the following ratio one mole
N2 : 3 moles H2.

4 : In the compressor, the gas mixture is heated to 450oC and 200 atm before it
enters the reactor chamber.

5 : In the reactor chamber, an iron catalyst helps to speed up the reaction.

N2(g) + 3H2(g)  2NH3(g)

 6 : The gases emerging from the reactor is cooled. Ammonia liquefies. The liquid
ammonia is separated. The unreactor nitrogen and hydrogen are returned to
the reactor via the compressor.

ALLOYS

o An alloy is a material that contains a mixture of elements and has metallic

properties.

Alloy Composition Properties Uses

Brass Copper 70% High strength Ornaments, door knobs,
Zinc 30% Resistance to bullet cases, electric
corrosion parts, musical
instruments.
Bronze Copper 90% High strength Medals, statues,
Tin 10% Resistance to monuments, art objects
corrosion
Duralumin Aluminium 95% Low density Aircraft, electric cable
Copper 5% High strength
Resistance to
corrosion
Pewter Tin 91% High strength Ornaments, souvenirs
Antimony 7% Resistance to
Copper 2% corrosion
Bright shiny surface
Steel Iron 99% High strength Car bodies, bridges,
Carbon 1% ships
Stainless Iron 80.6% Great resistance to Cutlery, sinks, knives,
steel Carbon 0.4% corrosions pipes
Chromium 18%
Nickel 1%
Table 1 compositions, properties and uses of alloys
 Figure 1 formation of Alloy

SYNTHETIC POLYMERS

o Synthetic polymers are made by man from chemicals obtained from

petroleum fractions, natural gas and coal.

o Synthetic polymers are used to make plastics, fibres, resins, and synthetic
rubbers.

Some Common Addition Polymers

Name(s) Formula Monomer Properties Uses

Polyethylene
ethylene film wrap, plastic
low density –(CH2-CH2)n– soft, waxy solid
CH2=CH2 bags
(LDPE)

Polyethylene electrical
ethylene rigid, translucent
high density –(CH2-CH2)n– insulation
CH2=CH2 solid
(HDPE) bottles, toys

atactic: soft,
Polypropylene similar to LDPE
–[CH2- propylene elastic solid
(PP) different carpet,
CH(CH3)]n– CH2=CHCH3 isotactic: hard,
grades upholstery
strong solid

Poly(vinyl
–(CH2- vinyl chloride pipes, siding,
chloride) strong rigid solid
CHCl)n– CH2=CHCl flooring
(PVC)

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

chloride) chloride
(Saran A) CCl2)n– CH2=CCl2 melting solid films

hard, rigid, clear

toys, cabinets
Polystyrene –[CH2- styrene solid
packaging
(PS) CH(C6H5)]n– CH2=CHC6H5 soluble in organic
(foamed)
solvents

Polyacrylonitrile high-melting solid

–(CH2- acrylonitrile rugs, blankets
(PAN, Orlon, soluble in organic
CHCN)n– CH2=CHCN clothing
Acrilan) solvents

non-stick
Polytetrafluoroe tetrafluoroeth
resistant, smooth surfaces
thylene –(CF2-CF2)n– ylene
solid electrical
(PTFE, Teflon) CF2=CF2
insulation

Poly(methyl methyl
–[CH2- lighting covers,
methacrylate) methacrylate hard, transparent
C(CH3)CO2C signs
(PMMA, Lucite, CH2=C(CH3)C solid
H3]n– skylights
Plexiglas) O2CH3

Poly(vinyl –(CH2- vinyl acetate

latex paints,
acetate) CHOCOCH3)n CH2=CHOCOC soft, sticky solid
adhesives
(PVAc) – H3

–[CH2- isoprene requires

cis-Polyisoprene
CH=C(CH3)- CH2=CH- soft, sticky solid vulcanization
natural rubber
CH2]n– C(CH3)=CH2 for practical use

Polychloroprene –[CH2- chloroprene

tough, rubbery synthetic rubber
(cis + trans) CH=CCl- CH2=CH-
solid oil resistant
(Neoprene) CH2]n– CCl=CH2

GLASS AND CERAMICS

Glass

Type of glass Composition Properties Uses

Fused glass SiO2: 100% • Transparent • Lens

• High melting • Telescope
 point mirrors
• Good heat • Laboratory
insulator apparatus
Soda-lime glass SiO2: 75% • Low melting • Drinking glass,
point, easily bottles
Na2O:15% molded into • Electric bulbs
desired shape • Window glass
CaO: 9% and size
• Low resistant to
Other:1% chemical attacks
• Brittle
Borosilicate glass SiO2: 78% • Resistant • Cooking utensils
chemical attack • Laboratory
B2O3: 12% and durable glassware such
• High melting as conical flaks
Na2O: 5% point and boiling tube
• Good insulator
CaO: 3%
to heat
Al2O3:2%

Lead crystal glass SiO2: 70% • High refractive • Lenses and

(flint glass) index prisms
Pbo/PbO2:20% • High density • Decorative
• Attractive glassware and
Na2O: 10% glittering art object
appearance • Imation jewellery

Ceramics

o Ceramics are a class of non-metal materials, which are better electrical and
thermal insulators then metals. They have greater rigidity, hardness and
resistance to heat and chemical attacks compared to organic polymers.

o Traditional silicate ceramics are made by heating aluminosilicate clay such as

kaolin to a very high temperature.
o Ceramics have many special properties that make them one of the most
useful materials in our everyday life. That are :

a.Are hard, strong but brittle

b. Have high melting point and remain stable at high temperature
c.Are heat and electric instrument
d. Are resistant to corrosion and wear
e.Are chemically not reactive
f. Do not readily deform under stress

o Ceramic play important role in our daily life. They are uses as

a.Construction materials
 i. Ceramic are strong and hard, uses to make roof tiles, bricks cement,
sinks, and toilet bowls.
ii. They are also used to make refractory bricks because high resistant to
heat.
b. Decorative items
i. 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 wall tiles.
c.Electrical insulator
i. Ceramic are used to make electrical insulator in electrical items such as
toasters, fridges and electrical plug.

Materials Melting Density/G Elastic Hardness/

point/ °C cm-3 modulus/ GPa mohs

Oxide ceramic

Alumina,AL2O3 2054 3.97 380 9

Beryllia, BeO 2574 3.01 370 8

Zirconia, ZiO 2710 5.68 210 8

Non-oxide
ceramics
2350 2.50 280 9
Boron carbide,B4C3
2830 3.16 400 9
Silicon nitride, Si3, n4
1900 3.17 310 9

Metals

Aluminium 660 2.70 70 3

Steel 1515 7.86 205 5

Comparing properties of glass and ceramics

Glass Similarities Seramics

 Strong under compression

 Hard
 Brittle
 Do not corrode
 Good electrical insulator
 Good heat insulator
  Resistant to chemical attacks

Highly transparent Differences Opaque

i. Optical
transparenc
y
Can be melted and ii. Moulding Cannot be melted and
remoulded remoulded
 References
Revision book
- Focus Excel Chemistry Form 4 , Penerbitan Pelangi
Sdn. Bhd. , First published 2006 , Eng Nguan Hong,
Lim Eng Wah, Lim Yean Ching
Internet
- Google search > manufactured substances in
industry