CONTENTPage

9.1 Sulphuric acid9.1.1 Properties of sulphuric acid

9.1.2 The uses of sulphuric acid

9.1.3 The industrial process in manufacture of sulphuric acid

9.1.4 Environmental pollution by sulphuric acid

9.2 Ammonia and its salt9.2.1 Properties of ammonia

9.2.2 The uses of ammonia

9.2.3 The industrial process in manufacture of ammonia

9.3 Alloys9.3.1 Arrangement of Atoms in Metals

9.3.2 What are Alloys

9.3.3 Composition, Properties, Uses of Alloys

9.4 Synthetic polymers9.4.1 What are Polymer, Properties of Polymers

9.4.2 Monomers in synthetic Polymers

9.4.3 Examples of Synthetic Polymers & Their Uses

9.5 Glass and ceramics9.5.1 Glass

9.5.2 Ceramics

9.6 Composite material

Conclusion of Topic

9.1 SULPHURIC ACID

9.1.1 Properties of sulphuric acid

1. Sulphuric acid is a strong mineral acid.

2. Its molecular formula is H2SO4.

3. It is soluble in water.

4. Sulphuric acid is a non-volatile diprotic acid.

5. It is a highly corrosive, dense and oily liquid.

6. Concentrated sulphuric acid is a viscous colourless liquid.

9.1.2 The uses of sulphuric acid

1) To manufacture fertilizers

There are many fertilizers that can be made of sulphuric acid. Some of them are:

a) Calcium dihydrogen phosphate (superphosphate)

2 H2SO4 + Ca3(PO4) 2 → Ca(H2 PO4) 2 + 2CaSO4

sulphuric acid + tricalcium phosphate → calcium dihydrogen phosphate

b) Ammonium sulphate

H2SO4 +2NH3 → (NH4) 2SO4 sulphuric acid + aqueous ammonia → ammonium sulphate

c) Potassium sulphate

H2SO4 +2NH3 → (NH4) 2SO4

sulphuric acid + aqueous ammonia → ammonium sulphate

2) To manufacture detergents

Sulphuric acid reacts with hydrocarbon to produce sulphonic acid. Sulphonic acid is then neutralized with sodium hydroxide to produce detergents. Examples of hydrocarbon

3) To manufacture synthetic fibres

Synthetic fibres are polymers ( long chain molecules). Rayon is an example of a synthetic fibre that is produced from the action of sulphuric acid on cellulose.

4) To manufacture paint pigments

The white pigment in paint is usually barium sulphate, BaSO4. The neutralization of sulphuric acid and barium hydroxide produces barium sulphate.

5) As an electrolyte in lead-acid accumulators

6) To remove metal oxides from metal surfaces before electroplating

7) To manufacture pesticides

8) The uses of sulphuric acid in school laboratories are:

a. As a strong acid

b. As a drying or dehydrating agent

c. As an oxidizing agent

d. As a sulphonating agent

e. As a catalyst

9.1.2 The industrial process in manufacture sulphuric acid

1. Sulphuric acid is manufactured by the Contact process.

2. Sulphuric acid is produced from sulfur, oxygen and water via the contact process.

3. The Contact process involves three stages.

Sulphur → Sulphur dioxide → Sulphur trioxide → Sulphuric

4. Stage I: Production of sulphur dioxide gas, SO2.

This can be done by two methods,

a) Burning of sulphur in dry air.

S + O2 → SO2

b) Burning of metal sulphide such as zinc sulphide in dry air.

2ZnS + 3O2 → 2SO2 + 2ZnO

5. Stage II: Conversion of sulphur dioxide to sulphur trioxide SO3.

This is then oxidised to sulfur trioxide under the following conditions:

a) The presence of a vanadium(V) oxide as a catalyst.

b) A temperature of between 450°C to 550°C.

c) A pressure of one atmosphere

2 SO2 + O2 → 2 SO3

6. Stage III: Production of sulphuric acid

a) Sulphur trioxide is dissolved in concentrated sulphuric acid, H2SO4 to produce oleum, H2S2O7

H2SO4+ SO3 → H2S2O7

b) Oleum is reacted with water to form concentrated H2SO4.

H2S2O7+ H2O → 2 H2SO4

7. In stage II, sulphur dioxide is dried first before being added to dry air to produce sulphur trioxide. This is:

a) To remove water vapour

b) To remove contaminants

8. In stage III, sulphur trioxide is not dissolved directly in water to produce sulphuric acid. This is because:

a) sulphur trioxide has low solubility in water

b) sulphur trioxide reacts violently and mists are formed instead of a liquid

Outline Of Contact process

Figure 9.5 Flowchart of Contact process

9.1.3 Environmental pollution by sulphuric acid

1. Sulphur dioxide is the main byproduct produced when sulfur-containing fuels such as coal or oil are burned.

2. Sulphuric acid is formed by atmospheric oxidation of sulphur dioxide in the presence of water. It also produces sulphurous acid.

3. Sulphuric acid and sulphurous acid are constituents of acid rain.

4. Acid rain can cause many effects such as:

i. Corrodes concrete buildings and metal structure

ii. Destroys trees and plants

iii. Decrease the pH of th soil and make it become acidic Acid rain flows into the rivers and increases the acidity of water and kill aquatic living things.

5. Hence, we must reduce the sulphur dioxide from the atmosphere by:

i. Use low sulphur fuels to reduce the emission of sulphur dioxide in exhaust gases

ii. Remove sulphur dioxide from waste air by treating it with calcium

9.2 AMMONIA AND ITS SALT

9.2.1 Properties of ammonia

1. A colorless, pungent gas.

2. Its molecular formula is NH3

3. It is extremely soluble in water.

4. It is a weak alkali.

6. It reacts with hydrogen chloride gas to produce white fumes of ammonium chloride.

NH 3 + HCl → NH4C

7. Ammonia is alkaline in property and reacts with dilute acids in neutralization to produce salts. For examples:

NH3 + HNO 3 → NH4NO 3

2NH3 + H2SO4 → (NH4) 2SO4

8. Aqueous solutions of ammonia produces OH − ions (except Na+ ion, K+ ion, and Ca 2+ ion) forming metal hydroxides precipitate.

Fe3+ + 3OH− → Fe(OH) 3 Brown precipitate

Mg2+ + 2OH− → Mg(OH) 2 White precipitate

9. Some metal hydroxides such as zinc hydroxide and copper (II) hydroxide dissolves in excess aqueous ammonia to form complexes.

Zn(OH) 2 + 4NH3→ [Zn(NH3)4] 2++ 2OH−

Cu(OH)2 + 4NH3→ [Cu(NH3)4] 2+ + 2OH−

USES OF AMMONIA IN INDUSTRY:

Examples are ammonium sulphate, ammonium nitrate and urea. The first two are prepare through neuralisation but urea is produced by the reaction of ammonia with carbon dioxide. The reaction involved are as the following: a) 2NH3 (g) + H2SO4 (aq) (NH4)2SO4 (s) ammonium sulphate b) NH3 (g) + HNO3 (aq) NH4NO3 (aq) ammonium nitrate c) 2NH3 (g) + CO2 (g) (NH2)2CO (s) +

H2O (l) urea

Having a low melting point, liquefied ammonia makes a good cooling agent in refrigerators and air conditioners.

It neutralizes the organic acids formed by microorganisms in latex, thereby preventing coagulation and preserving the latex in liquid form.

Ammonia is converted to nitric acid in the Ostwald process:

1) ammonia is first oxidised to nitrogen monoxide, NO, by oxygen in the presence of platinum as catalyst at 900˚C.

4NH3 (g) + 5O2 (g) Pt/900˚C 4NO (aq) + 6H2O (l) 2) nitrogen monoxide is further oxidised to nitrogen dioxide.

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

3) Nitrogen dioxide and oxygen are dissolved in water to produced nitric acid.

4NO2 (g) + O2 (g) + H2O (l) 4HNO3 (aq)

a) Nitric acid is manufactured from ammonia before being used to make explosive like trinitrotoluene (TNT).

b) Nitric acid, in this case, is reacted with organic substances like toluene.

9.2.3 The industrial process in manufacture of ammonia

1. Haber process is the industrial method of producing ammonia.

2. It needs direct combination of nitrogen and hydrogen under high pressure in the presence of a catalyst, often iron.

3. Nitrogen gas used in Haber process is obtained from the frictional distillation of liquid air.

4. Hydrogen gas used in Haber process can be obtained by two methods:

a) The reaction between steam and heated coke (carbon)

C + H2O → CO + H2

b) The reaction between steam and natural gas

( consisting mainly of methane)

CH4 + 2H2O → CO2 +

5. In the Haber process:

a) A mixture consisting of one volume of nitrogen gas and three volume of hydrogen gas is compressed to a pressure between 200 – 500 atmospheres.

B) The gas mixture is passed through a catalyst of powdered iron at a temperature of 450 - 550°C.

c) At this optimum temperature and pressure, ammonia gas is produced.

N2+ 3H2 → 2NH3

9.3 ALLOYS

9.3.1 ARRANGEMENT OF ATOMS IN METALS

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.

9.3.2 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.

9.4 SYNTHETIC POLYMERS

9.4.1 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.

9.4.2 Monomers and repeat units

The identity of the monomer residues (repeat units) comprising a polymer is its first and most important attribute.

Polymer nomenclature is generally based upon the type of monomer residues comprising the polymer.

Polymers that contain only a single type of repeat unit are known as homopolymers, while polymers containing a mixture of repeat units are known as copolymers.

Poly(styrene), for example, is composed only of styrene monomer residues, and is therefore classified as a homopolymer.

Ethylene-vinyl acetate, on the other hand, contains more than one variety of repeat unit and is thus a copolymer.

Some biological polymers are composed of a variety of different but structurally related monomer residues;

for example, polynucleotides such as DNA are composed of a variety of nucleotide subunits.

A polymer molecule containing ionizable subunits is known as a polyelectrolyte or ionomer

9.5 GLASS AND CERAMICS

1. The main component of both glass and ceramic is silica or silicon dioxide, SiO2.

2. Both glass and ceramic have the same properties as follow

a) Hard and brittle

b) Inert to chemical reactions

c) Insulators or poor conductors of heat and electricity

d) Withstand compression but not stretching

e) Can be easily cleaned

f) Low cost of production

3. Differences between glass and cerement are, glass is transparent, while ceramic is opaque. Ceramic can withstand a higher temperature than normal glass.

4. Types of glass are

a) Fused glass

• It is consist mainly of silica or silicon dioxide

• It has high heat resistance

b) Soda lime glass

• It cannot withstand high temperatures

c) Borosilicate glass

• It can withstand high temperature

d) Lead glass

• High refractive index

5. Uses of improved glass for specific purpose

a) Photochromic glass

• It is sensitive to light intensity

b) Conducting glass

• It conducts electricity

6. Ceramic is a manufactured substances made from clay, with the main constituent of aluminosilicate with small quantity of sand and feldspar.

7. Superconductor is one improved ceramics for specific purposes.

GLASS

Glass:-

• The major component of glass is silica or silicon dioxide, SiO2 which found in sand.

CERAMICS

Ceramics:-

• Ceramic is manufactured substances made from clay that is dried, and heated in a kiln at a very high temperature

• The main component of clay is aluminosilicate (aluminum oxide and silicon dioxide) with small quantities of sand and feldspar. Unlike glass, ceramic cannot be recycled.

• Kaolinite is a high quality white clay that contains hydrated aluminosilicate, Al2O3•2SiO2•2H2O.

THE DIFFERENT CLASES OF CERAMIC

GROUP COMPOSITION

Mineral Quartz – SiO2 Calcite – CaCO3

Cement material Mixture of CaSiO3 and ammonium silicate

Oxide of ceramic Aluminium oxide – Al2O3 Silicon dioxide – SiO2

Magnesium oxide – MgO

Non-oxides of ceramic Silicon nitride – Si3N4 Silicon carbide – SiC

Boron nitride – BN

Boron carbide – B4C3

THE USES OF IMPROVED GLASS AND CERAMICS FOR SPECIFIC PURPOSES

9.6 COMPOSITE MATERIAL

9.6.1 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

CONCLUSION OF TOPIC

We must appreciate these various synthetic industrial materials. One of the way is by doing continuous research and development ( R & D ) to produce better materials used to improve our standard of living. As we live in a changing world, our society is getting more complex. New materials are required to overcome new challenges and problems we face in our daily lives. Synthetic material are developed constantly due to the limitation and shortage of natural materials. New technological developments are used by scientists to make new discoveries.

New materials for clothing, shelter, tools and communication to improve our daily life are developed continuously for the well-being of mankind. New needs and new problem will stimulate the development of new synthetic materials. For example, the new use of plastic composite material will replace metal in the making of a stronger and lighter car body. This will save fuel and improve speed. Plastic composite materials may one day used to make organs for organ transplant in human bodies. This will become necessity with the shortage of human organ donors.

The understanding of the interaction between different chemicals is important for both the development of new synthetic materials and the disposal of such synthetic materials as waste. A responsible and systemic method of handling the waste of synthetic materials and their by-product is important to prevent environmental pollution. The recycling and development of environmental friendly synthetic material should be enforced.

PRODUCTION AND MANAGEMENT OF MANUFACTURED CHEMICALS

NAME MOHAMMAD AMIR HAKIMI BIN ABDUL RAHIM

CLASS 5 ARIF

SUBJECT CHEMISTRY

TEACHER PUAN FARIDATUL