Manufactured Substances in Industry

Glass It is a mixture of two or more types of metallic silicates but the main component is silicon(IV) dioxide. Glass has the following properties: Transparent and not porous Inactive chemically Can be cleaned easily Good insulators of heat and electricity Hard but brittle Can withstand compression but not pressure Soda lime glass Produced by … Read more

The most important component of glass and ceramics is silica ( silicon(IV) dioxide, SiO2). Both glass and ceramic have the following properties: Hard and brittle Do not conduct heat and electricity Inactive towards chemical reactions Weak when pressure is applied Can be cleaned easily

Issue in Using Synthetic Polymers Synthetic polymers have multiple uses in daily life because of the following properties: Light and strong Relatively cheap Withstand corrosion and chemical reaction Withstand action of water Non-flammable Can be colour easily Easily mould to shape Synthetic polymers are also used to replace natural polymers such as cotton, silk and … Read more

Synthetic Fibre Nylon and terylene are synthetic fibres which undergo the condensation polymerisation process. These fibres resemble natural fibres but more resistant to stress and chemicals, and more long-lasting.  In both cases, water is eliminated during the polymerisation process. Nylon Structure Monomer: Produced by polymerisation: CondensationUses: To make umbrellas, carpets, comb, curtains, nylon string and rope, socks, … Read more

Synthetic Rubber Synthetic rubber is an elastomer or polymer which regains its size original shape after being pulled or pressed. [Natural rubber is an elastomer too.] Examples of synthetic rubber are neoprene and styrene-butadiene(SBR). Neoprene Structure Monomer: ChloropreneProduced by polymerisation: AdditionUses: to make rubber gloves and to insulate electric wires. Styrene-butadiene or SBR Structure Monomer: Styrene … Read more

Plastics Plastics are light, strong and do not react with any chemical substances, like acids and alkalis. They can be made into many shapes and sizes. They are also good insulators of heat and electricity. Examples of Plastics: Polythene (polyethylene) Structure Monomer: EtheneProduced by polymerisation: AdditionUses: Plastic bags containers and cupsAdvantages:  light and strong Polyvinyl chloride … Read more

Polymerisation Polymerisation is the process of joining together the large number of monomers to form a polymer. There are 2 types of polymerisation process polylerisation by addition polylerisation by condensation Polylerisation by Addition Polymerisation by addition involves monomers with >C = C< bonding, where the monomers join together to make a long chain without losing … Read more

Polymer Polymer is a large molecule that is in the form of a long chain with a high relative molecular mass (RMM). It is made up of many smaller units called monomers, which are joined together through a process called polymerisation. Thus the monomer is actually the repetitive unit of a long polymer chain. There … Read more

Tin Based Alloy Examples of tin base alloy are pewter solder Most tin base alloy has shiny surface and low melting point. Pewter Component: Sn 91%, Sb 7%, Cu 2% Applications: Decorative items, souvenirs Solder Component: Sn 50%, Pb 50% Applications: Welding and soldering work （Welding） (Soldering)

Aluminium Bases Alloy Examples of aluminium base alloy are Duralumin Magnalium Aluminium has low density, hence the density of aluminium base alloy is also low. Duralumin Component: Al 95%, Cu 4%, Mg 1% Applications: Aeroplane parts, electric cables, racing bicycles Magnalium Component: Al 70%, Mg 30% Applications: Tyre rim of racing cars, skeletal body of aeroplanes