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 Understand the manufacture of sulphuric acid.
 Synthesise 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 materiala.




                                                         1
                                     (H4SO4)
    USES OF SULPHURIC ACID

    1. Sulphuric acid is used to produce chemical fertilizer such as ammonium sulphate and
       potassium sulphate, which are highly soluble 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
       their component materials.




 MANUFACTURE OF SULPHURIC ACID
 1. Sulphuric acid is manufactured in industry though contact process
 2. The process contain three stage

 STAGE1: Production Of Sulphur Dioxide From Sulphur
   i.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 Dioxide
      i.The purified sulphur dioxide SO2 and excess air are passed over vanadium(V) oxide
          V2O5 at controlled optimum condition optimum condition to produce sulphur
          trioxide SO3.
                                   2SO2(g)+O2(g) 2SO3(g)
     ii.The optimum used are
      a) Temperature:450-500°C
      b) Pressure: 2-3 atmospheres
      c) Catalyst: Vanadium(V) oxide
  iii.Under controlled optimum conditions, 98% conversion is possible. Sulphur dioxide and
         oxygen that have not reacted are allowed to flow back again over the catalyst in the
         converter.




                                                                                             2
STAGE3: Conversion of trioxide to sulphuric acid
 i. Sulphur trioxide SO2 is dissolved in concentrated sulphuric acid H2SO4 to form oleum
    H2S2O7 which is then diluted with water to form sulphuric 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 trioxide directly into water.

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

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




                                   The Contact Process


 Sulphu         Oxyge
 r              n
                                      In the converter
 S(s) + O2(g)SO2(g)                  2SO(g) + O2(g) 2SO3(g)
                                      Temperature: 450-500°C
                                      Pressure: 2-3 atmospheres                     Unreacted
                Oxyge                 Catalyst: Vanadium(V) oxide                   2%so2 is
                                                                                    flowed back
                                                                                    to converter
                                                                                    together with
                                      SO2(g) + H2SO4(aq)H2S2O7(l)                  oxygen
                                      H2S2O7(l) + H2O(l)2H2SO4(aq)


                                Outline Of Contact process
                                                                                            3
 SULPHUR DIOXIDE AND ENVIRONMENTAL POLLUTION
     1. Sulphur dioxide is one of the by-product of contact process. It is a colourless 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 easily oxidised in the air to form sulphur
        trioxide. Sulphur trioxide dissolve in rainwater to produce sulphuric acid.

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




                              Acid rain and environmental pollution




                                                                                                  4
                                       (NH3)
 USES OF AMMONIA
 1. Ammonia that is produce commercially has many uses.
 2. It uses:
        i.In the manufacture of chemical fertilizers such as ammonium sulphate, ammonia
          nitric, ammonia phosphate and urea.
       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.

 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 35.5°C) 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 to become alkaline. Thus
     aqueous ammonia solution:
      i. Turns red litmus paper blue.
     ii. Reacts with acid to form only salt and waterin neutralization reaction.

                               NH3(aq) + HCI(aq)  NH4CI(aq)
                             2NH3 + H2SO4(aq)  (NH4)2SO4(aq)

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

                              Fe²+(aq) + 2OH-(aq)  Fe (OH)2(s)
                                        (Form ammonia solution)   Dirty green precipitate




                                                                                            5
 MANUFACTURE OF AMMONIA IN INDUSTRY
  1. Ammonia is manufacture on a large scale in industry through the haber process. In this
     process, ammonia is formed form direct combination 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 from the 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 iron catalyst under
    controlled optimum condition as below to form ammonia gas.
        i. Temperature: 450-500°C
       ii. Pressure: 200-500 atmospheres
      iii. Catalyst used: Iron fillings

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

 4. Under these control optimum condition, only 15% of the gas mixture turn into ammonia
    gas. The nitrogen and hydrogen that have not reacted are then flow back over the catalyst
    again in the reactor chamber.
 5. The ammonia product is then cooled at a low temperature so that it condenses into a
    liquid in the cooling chamber.




                                    The Haber Process




                                                                                           6
                      Nitrogen                           Hydrogen



                     N2 and H2 are mixed in the proportion of 1:3

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

                                                    In cooling chamber

                                       Liquid ammonia


                               Outline Of Habert process


 AMMONIUM FERTILIZERS
1.   Nitrogen is required in large amount by plant to make proteins which are necessary
     for growth and cell repair.
2.   Most plant are not able to get a nitrogen supply directly from the air although it is
     abundant in the air (78%). Plants can only absorb soluble nitrogen compounds from
     soil through their roots.
3.   The nitrogen compounds are usually soluble nitric salt, ammonia and ammonia salt
     which are manufacture as chemical fertilizer.
4.   Reactions of ammonia with acids produce ammonium 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




                                                                                        7
    ARRANGEMENT OF ATOMS IN MATELS
   1.   The atom of pure metals are packed together closely. This causes the 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 that the 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 by vibration. This
        make metal good conduct of heat.
   4.   The freely moving outermost electrons within the metal’s structure are able to conduct
        electricity. Metal are, therefore, good electrical conductors.
   5.   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




                                                                                    The shape of the
Force                                                                               metal change




                                       Matel are malleable
                                                                                            8
 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.




                                                                                              9
     Alloy              Composition             Properties               Uses
High carbon steel         99% iron         Strong,hard and high  Making of cutting
                         1% carbon            wear resistance     tools, hammers
                                                                  and chisels
 Stainless steel         80.6% iron           Do not rust and    Making of surgical
                        0.4% carbon         tarnish, strong and   instrument, knives
                       18%chromium                durable         forks and spoons
                         1% nickel
     Brass              70% copper           Hard, do not rust,   Making of
                          30% zinc           bright appearance     ornaments,
                                                                   electrical wiring
                                                                   and plug.
     Bronze             90% copper         Hard, do not corrode  For casting bells,
                          10% tin            easily and durable    medals, swords
                                                                   and statues
     Pewter               90% tin               Ductile and       Making of
                        2.5% copper           malleable, white     ornaments,
                      0.5% antimony         silvery appearance     souvenirs and
                                                                   mugs
   Duralumin          95% aluminium           Light, strong and   Making part of
                         4% copper                 durable         aircrafts and racing
                       1%magnesium                                 cars
  Cupronickel            75%copper           Attractive, silvery  Making of silver
                         25%nickel         appearance, hard and    coins
                                                    tough
                    Composition, properties and uses of alloys




                               The formation of alloy


                                                                                    10
 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.

                           Some Common Addition Polymers
     Name(s)           Formula         Monomer            Properties                 Uses
Polyethylene
                     –(CH2-         ethylene                                   film wrap,
low density                                           soft, waxy solid
                     CH2)n–         CH2=CH2                                    plastic bags
(LDPE)
Polyethylene                                                                   electrical
                     –(CH2-         ethylene          rigid, translucent
high density                                                                   insulation
                     CH2)n–         CH2=CH2           solid
(HDPE)                                                                         bottles, toys
                                                      atactic: soft, elastic   similar to
Polypropylene
                     –[CH2-         propylene         solid                    LDPE
(PP) different
                     CH(CH3)]n–     CH2=CHCH3         isotactic: hard,         carpet,
grades
                                                      strong solid             upholstery
Poly(vinyl
                     –(CH2-         vinyl chloride                             pipes, siding,
chloride)                                             strong rigid solid
                     CHCl)n–        CH2=CHCl                                   flooring
(PVC)
Poly(vinylidene                     vinylidene
                     –(CH2-                           dense, high-             seat covers,
chloride)                           chloride
                     CCl2)n–                          melting solid            films
(Saran A)                           CH2=CCl2
                                                      hard, rigid, clear
                                                                               toys, cabinets
Polystyrene          –[CH2-      styrene              solid
                                                                               packaging
(PS)                 CH(C6H5)]n– CH2=CHC6H5           soluble in organic
                                                                               (foamed)
                                                      solvents
Polyacrylonitrile    –(CH2-         acrylonitrile     high-melting solid       rugs, blankets



                                                                                                11
(PAN, Orlon,        CHCN)n–         CH2=CHCN         soluble in organic   clothing
Acrilan)                                             solvents
                                                                          non-stick
Polytetrafluoroet                tetrafluoroethyl
                                                  resistant, smooth       surfaces
hylene              –(CF2-CF2)n– ene
                                                  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        CH2=CHOCO        soft, sticky solid
                                                                          adhesives
(PVAc)              )n–             CH3
                                                                          requires
                    –[CH2-     isoprene
cis-Polyisoprene                                                          vulcanization
                    CH=C(CH3)- CH2=CH-               soft, sticky solid
natural rubber                                                            for practical
                    CH2]n–     C(CH3)=CH2
                                                                          use
Polychloroprene     –[CH2-          chloroprene                           synthetic
                                                     tough, rubbery
(cis + trans)       CH=CCl-         CH2=CH-                               rubber
                                                     solid
(Neoprene)          CH2]n–          CCl=CH2                               oil resistant
                               Uses of synthetic polymers



 SYNTHETIC POLYMERS IN DAILY LIFE
1. Synthetic polymers have many advantages over other type of materials:
     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 synthetic polymer material
         catches fire, poisonous fumes are produce causing air pollution.
     b. Synthetic polymers are non-biodegradable. When there are discharge, they cause
         litter problem and pollute the environment.
     c. Plastic container that are left aside in an open area collect rainwater which
         becomes the breeding ground for mosquitoes.
     d. There are limitation in recycle have to be separated out as the addition of non-
         recyclable polymers in the mixture affect the properties of the recycled polymers.




                                                                                          12
 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 specials properties.
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           Lens
                                              High melting point    Telescope mirrors
                                              Good heat             Laboratory
                                               insulator              apparatus
  Soda-lime glass          SiO2: 75%          Low melting point,    Drinking glass,
                           Na2O:15%            easily molded into     bottles
                            CaO: 9%            desired shape and     Electric bulbs
                           Other:1%            size                  Window glass
                                              Low resistant to
                                               chemical attacks
                                              Brittle
 Borosilicate glass        SiO2: 78%          Resistant chemical    Cooking utensils
                           B2O3: 12%           attack and durable    Laboratory
                           Na2O: 5%           High melting point     glassware such as
                            CaO: 3%           Good insulator to      conical flaks and
                           Al2O3:2%            heat                   boiling tube
 Lead crystal glass        SiO2: 70%          High refractive       Lenses and prisms
    (flint glass)        Pbo/PbO2:20%          index                 Decorative
                          Na2O: 10%           High density           glassware and art
                                              Attractive             object
                                               glittering            Imation jewellery
                                               appearance




                                                                                     13
 CERAMICS
1. Traditional silicate ceramics are made by heating aluminosilicate clay such as kaolin to
   a vary high temperature.
2. Ceramics have many special properties that make them one of the most useful materials
   in our everyday life. That:
     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
3. 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 point/     Density/G cm-3        Elastic         Hardness/ mohs
                         °
                           C                              modulus/ GPa
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
Boron                    2350               2.50                280                 9
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




                                                                                           14
 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

 REINFORCES CONCRETE
1. Concrete is hard, fireproof, waterproof, comparatively cheap and easy to maintain. It is
   more important construction materials.
2. The reinforces is a combination of concrete and steel.

 SUPERCONDUCTOR
1. Metal such as copper and aluminium are good conductor of electricity, but 20% of the
   electric energy is lost in the form of heat during transmission.
2. Super conductor are materials that have no resistance to the flow of electricity at a
   particular temperature. Hence, 100% electricity transmission is possible.
3. One of the most dramatic properties of a superconductor is its ability to levitate a
   magnet. Superconductor are used to build magnetically levitate high-speed train (at
   about 552 km/h).
4. Superconductor are used to make chips for smaller and faster supercomputer.
   Superconductor also play an important role in high speed data processing in internet
   communication.

 FIBRE OPTIC
1. Fibre optic is a composite material that in used to transmit signals for light wave.
2. Fibre optic is used in
  a. Telecommunicate where the telephone substation are liked by fibre optic cables.
  b. Domestic cable television network
  c. Closed circuit television security system.
3. Fibre optic also used in medical fields. It is used in a number of instrument which
   enable the investigation for internal body part without having to perform surgery.




                                                                                        15
 FIBRE GLASS
1. Fibre glass is glass in the form of fine threads. Molten gas is dropped onto a refractory
   rating disc when the glass flies off the disc glass to form fibre.
2. Fibre glass is strong than steel, do not burnt, stretch or rot, resistant to fire and water but
   is brittle.
3. When fibre glass added to a plastic, a new composite material fibre glass reinforces
   plastic is formed.
4. Fibre glass reinforces plastic has more superior properties than glass and plastic. It is
      a. Extremely strong
      b. Light weigh
      c. Resistant to fire and water
      d. Can be molded, shaped and twisted

 PHOTOCHROMIC GLASS
1. When 0.01 to 0.1% of silver chloride (a type of photochromic substances) and a small
   amount of copper (II) chloride are added to molten silicon dioxide, photochromic glass
   is formed.
2. The photochromic glass has a special properties. It darken when exposed to strong
   sunlight or ultraviolet.
3. Photochromic glass is suitable for making sunglasses.




                                                                                               16

				
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