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Science Form 4 Chapter 9: Chemicals in Industry - Coggle Diagram
Science Form 4
Chapter 9:
Chemicals in Industry
Alloy
Purpose
To prevent corrosion or rusting
To prevent corrosion or rusting
To increase the hardness and strength of metal
Properties
Bronze
Tin 12%
Hard
Copper 88%
Resistant to corrosion
Attractive colour
To make monuments, metak sculptures, coins, medals and others
Brass
Copper 75%
Zinc 25%
Strong
Has shony surface
Malleable
Gold in colour
To make keys, door knobs, musical instruments such as trumpet
Duralumin
Copper 3%
Magnesium 1%
Aluminium 95%
Manganese 1%
Light
Strong
Corrosion resistant
To make frame of aircrafts, aeroplanes and others
Steel
Iron 99%
Carbon 1%
Hard and strong
Construction materials for building and bridge
To make frame of vehicles and railway tracks
Pewter
Tin 96%
Cooper 3%
Antimony 1%
Lustre
Resistant to corrosion
To make decorative items such as photo frame
Characteristics
harder
corrosion resistant
stronger
shiny
An alloy is a mixture of several types of metals or a mixture of metal and non-metal by a certain percentage
Glass and Ceramic
Type of glass
Soda-lime glass
Composition
calcium carbonate
sodium carbonate
Silica
Properties
low melting point
easy to shape
Borosilicate glass
Composition
Boron oxide
sodium oxide
Silica
aluminium oxide
Properties
High resistance to heat and chemicals compared to soda-limed glass
Fused silica glass
Composition
Silica
Properties
Chemically inert
Resistant to heat
Lead crystal glass
Composition
Silica
Lead(II) oxide
Sodium oxide
Properties
High refractive index
Low melting point
Application of glass
Application of ceramic
Glass made of silica - contains silicon oxide
Polymer
A large molecule formed by chains of monomer
Natural Polymer
Protein
Build cells and body tissues
Natural rubber
To make rubber-based products
Starch
Produces energy
Polymer that exist naturally
Synthetic Polymer
Man-made polymers using chemical susbtances
Polythene
To make plastic bottles, plastic bags and pails
Polystyrene
To make packing container for electrical equipment
Perspex
To make aeroplane mirrors, windows for vehicles
Synthetic rubber
To make gloves, tyres and shoe soles
Polymerisation
the process of joining the monomers through the formation of chemical bonds to produce a long-chain polymer
Depolymerisation
the process of splitting a long chain polymer into its monomer through chemical reactions