CHEM PRESENTATION CHAPTER 8

CHAPTER 8:
MANAFACTURED

SUBSTANCES IN
INDUSTRY

CHAPTER 8.1:
ALLOY AND ITS
IMPORTANCE

ALLOY is a mixture of two
or more elements where
the main element is metal.

ALLOY USE
DURALUMIN
Used to make the
BRONZE body of an
BRASS aeroplane
STEEL
Used to make
medals
Used to make keys

Used to make the
body of a car

STAINLESS STEEL Used to make
PEWTER cutlery

Used to make
souvenirs

COMPARISON OF
PROPERTIES OF
AN ALLOY AND A

PURE METAL

The alloying process
helps to prevent the
corrosion of metal and
alter the properties of
a pure metal to make
it harder and stronger.
How did these
changes happen?

Alloy Pure metal

Shiny Surface Dull

Resistant Resistance of Easily
to corrosion corroded

corrosion Hardness Less
hard
Hard

PURE METALS ARE
DUCTILE AND
MALLEABLE

JUSTIFY THE USES
OF ALLOYS BASED

ON THEIR
COMPOSITION AND

PROPERTIES

Composition, properties
and the uses of alloys

◦The uses of alloys is based on the
composition and properties of the
alloy produced. Alloys are made for
specific purposes. Scientists change
the elemental composition to
produce alloys with different
properties. For example, steel and
stainless steel originate from the
same pure metal l, which is iron.
However, both alloys have different
properties and are used for
different purposes.

Composition, properties
and the uses of alloys

8.2:
Composition Of
Glasses and Its

Uses

Glass, something that we see
everyday. Did you know how
glass is formed? Well, when
silica is heated together with
other chemicals, different
types of glasses are formed.

Basic Properties of Glass

= When silica is heated together with
other chemicals, various types of
glass with different properties are
obtained. However, all types of glass
have the same basic properties.

• Hard but Brittle

• Chemicaly Inert

• Transparent

• Waterproof

• Heat Insulator

• Electrical Insulator

Types of Glasses

TYPES OF GLASSES

1. Fused Silica Glass
2. Soda-Lime Glass
3. Borosilicate Glass
4. Lead Cyrstal Glass

Fused Silica Glass

Made from:
• Silica

( Silicon Dioxide , SiO2 )

Silica, SiO2 requires high temperature
around 1800°C to melt. Hence, fused
silica glass has a high melting point.
The glass does not expand nor
contract much when there is a large
change in temperature. Fused silica
glass is suitable to be used in making
telescope lens.

Soda-lime Glass

Made from
• Silica

( Silicon Dioxide , SiO2 )
• Soda

( Sodium Carbonate, Na2CO3 )
• Limestone

( Calcium Carbonate, CaCO3 )

Soda, Na2CO3 lowers melting point of
silica, siO2.It has a low melting point,
around 1000 C. It is composed of
about 70 percent silica (silicon
dioxide), 15 percent soda (sodium
oxide), and 9 percent lime (calcium
oxide), with much smaller amounts of
various other compounds. This glass is
easily moulded and used to make
glass containers such as bottles and
jugs. However, this glass cannot
withstand high temperatures and can
easily crack when subjected to sudden
temperature change.

Glass Containers
Glass Panels

Boroslicate Glass

Made from
• Silica

( Silicon Dioxide, SiO2 )
• Soda

(Sodium Carbonate, NaCO3)
• Limestone

(Calcium Carbonate, CaCO3)
• Boron Oxide, (B2O3)
• Aluminium Oxide, Al2O3

Many laboratory glassware such as beakers
and flasks are made from borosilicate glass
such as Pyrex or Hysil, although a certain
amount of soda glass apparatus is still used.
because of its resistance of heat. These
glassware do not crack easily when subjected
to thermal stress because of its low expansion
coefficient. Borosilicate glass can be removed
from the refrigerator and heated immediately.

Laboratory Glassware
Flasks

Lead Crystal Glass

Made from
• Silica

( Silicon Dioxide, SiO2 )
• Soda

( Sodium Carbonate, Na2CO3 )
• Lead Oxide,( PbO )

Lead, Pb replaces Calcium, Ca to produce
glass that is softer and denser. Lead glass is
heavier and has a high refractive index. This
glass is suitable to be used in making
prisms.Thus, the presence of lead is used in
glasses absorbing gamma radiation and X-
rays, used in radiation shielding as a form of
lead shielding

Chemistry
presentation

CHAPTER 8 :
MANUFACTURED
SUBSTANCES IN
INDUSTRY

SUBTOPIC 8.3 :
COMPOSITION OF
CERAMICS AND ITS
USES

GROUP MEMBERS :

-JOHN PAAUL

-SUESHAN SANMUGAM

-VEVALAKSHAN
VIJAYAKUMAR

-DESRRAN PEREIRA

-AJAY VHARMAN

-THIVIYA TAMILVANAN
-SHAMMINISRI SREE
SHANKER

-VEAKA KALAISELVAM

-TARINIE KUMAR

8.3-
COMPOSIT ION
OF CERAMICS
AND ITS USES

-MEANING OF
CERAMICS

-BASIC OF
PROPERTIES
CERAMICS

-TYPES OF
CERAMICS

-CERAMIC USES
APPLICATIONS

MEANING
OF

CERAMICS

A CERAMIC IS
A SOLID MADE
UP OF
INORGANIC
AND NON-
METALLIC
SUBSTANCES.
CERAMICS IS
PRODUCED
THROUGH THE
PROCESS OF
SHAPING AND
HARDENING BY
USING
HEATING
TECHNIQUE AT
A HIGH
TEMPERATURE.
MOST
CERAMICS ARE
MADE UP OF
METAL
COMPOUNDS,
NON-METAL
COMPOUNDS
OR METALLOID
COMPOUNDS.

EXAMPLES OF
CERAMIC
PRODUCTS

1) ALUMINIUM OXIDE
2) TITANIUM
CARBIDE

3) SILICON CARBIDE

BASIC
PROPERTIES OF

CERAMICS

THE ATOMS IN

CERAMICS ARE

BONDED BY STRONG

COVALENT BONDS

AND IONIC BONDS.

HENCE, CERAMICS

ONLY MELT AT VERY

HIGH

TEMPERATURES, ARE

HARD AND

RESISTANT TO

COMPRESSION.

WHEN FORCE IS

APPLIED, THE

ATOMS IN

CERAMICS CANNOT

SLIDE OVER

BECAUSE THESE

ATOMS ARE

STRONGLY BONDED

IN INDEFINITE

ARRANGEMENT. THE

ENERGY FROM THE

FORCE WILL BE

USED TO BREAK THE

BONDS BETWEEN

THE ATOMS. HENCE,

CERAMICS ARE

BRITTLE AND WEAK

TOWARDS

STRETCHING. THE

ELECTRONS IN

CERAMICS CANNOT

MOVE FREELY TO

CONDUCT

ELECTRICITY OR

HEAT ELECTRICITY OR HEAT

OR HEAT.

BASIC
PROPERT IES

OF
CERAMICS

-HIGH THERMAL
RESISTANT

-HEAT
INSULATOR

-HARD AND
STRONG

-ELECTRICAL
INSULATOR

- C H E M I C A L LY
INERT

-BREAK EASILY

TYPES OF
CERAMICS

- TRADITIONAL
CERAMICS

- - ADVANCED CERAMICS

TRADIT IONAL
CERAMICS

- MADE UP OF CLAY
SUCH AS KAOLIN

- MIXED WITH WATER
TO PRODUCE A SOFT,
MOULDABLE MIXTURE

- THE MIXTURE IS
THEN HEATED AT A
VERY HIGH
TEMPERATURE

- TRADITIONAL
CERAMICS ARE USED
TO MAKE BRICKS,
POTTERY AND
COOKERY

- BIO-INERT, WITH
INHERENT PROPERTIES
OF HIGH HARDNESS,
AND HIGH
COMPRESSIVE
STRENGTHS COUPLED
WITH LOW
COEFFICIENTS OF
FRICTION WHICH MAKE
THEM SUITABLE FOR
HARD TISSUE AND
JOINT REPAIRS

ADVANCED
CERAMICS

- MADE OF INORGANIC
COMPOUND SUCH AS
OXIDES, CARBIDES
AND NITRIDES

- HAVE HIGHER
RESISTANCE TO HEAT
AND ABRASION

- CHEMICALLY MORE
INERT AND
SUPERCONDUCTIVITY

- ADVANCED
CERAMICS ARE
DENSIFIED FROM
POWDERS BY
APPLYING HEAT (A
PROCESS KNOWN AS
SINTERING)

CERAMIC USES
APPLICAT ION

8.4 Composite
Materials and Its

Importance

a) Give the meaning and
properties of composite
materials.

b) Explain with example
the uses of composite
materials.

c) Compare and contrast
the properties of a
composite material
with its constituent
materials.

What is a composite material ?

= A composite material is a
material made from combining
two or more non-homogeneous
substances, that is matrix
substance and strengthening
substance. The matrix
substance surrounds and binds
the strengthening substance
together.

Properties of composite
materials (these properties differ for every

composite material)

• High compression strength
• High stretching strength
• Resistant to corrosion
• Durable
• Flexible
• Transparent
• Heat and electrical insulator

Examples and Uses of Composite Materials

-Composite materials are widely used in the development
and advancement of technology nowadays.

1.Reinforced concrete: Produced when steel bars or wire
mesh (strengthening substance) is immersed in concrete
(matrix substance). Reinforced concrete is widely used in
the construction of; bridges, dams and buildings.

2.Fibre glass: Produced when plastic (matrix substance) is
strengthened with glass fibres (strengthening substance).
This composite material is used to make helmets, car
bumpers and printed circuit boards.

3.Optical fibre: Consists of three layers; silica glass fibres
(strengthening substance), glass or plastic (matrix
substance), plastic as a protective jacket (matrix substance).
Optical fibres are used to transfer information and data in
the form of light. Optical fibre is being used in; video
cameras and cables in computer network as a replacement
for copper.

4.Photochromic glass: Formed when glass (matrix
substance) is combined with silver chloride, AgCl and
copper(1) chloride, CuCl (strengthening substance).
Photochromic glass protects the user from UV rays by
darkening when it is exposed to sunlight. This composite
material is suitable for use in; car windows, building
windows and camera lenses.

5.Superconductors: For example, yttrium barium copper
oxide,YBCO ceramic is a composite material that has
superconductivity properties other than alloys.
Superconductor is used to make electromagnets, that are
supermagnets. Superconductor magnets are in particle
accelerators and involved in Nuclear Magnetic Resonance
(NMR) machines and Magnetic Resonance Imaging (MRI)
machines.

Comparison and Difference in
Properties of Composite Materials
and Their Original Components

Comparison in properties of reinforced
concrete with its original components

Concrete can withstand high
compression forces but will break if
subjected to high stretching forces.
Combination of concrete and steel bars
or wire mesh can increase the ability of
the concrete to withstand compression
forces.

Properties Concrete Reinforced Properties
• High concrete • High
Steel compressi
compression bars or on
strength
wire +strength
• Low stretching mesh
strength • High
stretching
• Resistant to strength
corrosion • Resistant

Properties to
• High corrosion

stretching
strength
• Corrodes

easily

Comparison in properties of fibre glass
with its original components

Plastic matrix consists of plastic that is
weak, soft and easily burned. The
properties of plastic are reinforced by
adding glass fibres.

Properties Plastic Properties
• Low stretching
Fibre • High
strength Glass stretching
• Low heat and strength
Glass • Heat and
electrical fibre electrical
conductivity insulator
• Resistant to • Resistant

corrosion to
• Durable corrosion
• Durable
Properties
• High
stretching
strength

• Low heat and
electrical

conductivity

Comparison in properties of optical
fibre with its original components

Optical fibre has high compression
strength although the original
component that is glass fibre, is brittle.

Properties Plastic Properties
• High
Optical • High
compression Fibre compres
strength
Fibre sion
• Flexible Glass strength
• Flexible
Properties
• Low

compression
strength
• Hard

Comparison in properties of
photochromic glass with its original
components

Glass is transparent and does not
absorb UV rays. Silver halide salt
crystals such as silver chloride, AgCl
is transparent to visible light and
absorbs UV rays at the same time.

Properties Glass Properties
• Transparent
Photochromic • Transparent
• Does not glass
absorb UV • Absorbs UV
Silver rays
rays Chloride
• Not sensitive • The
absorption
to light of UV rays
depends on
Properties
• Transparent to light
intensity
visible light
• Absorbs UV

rays
• Sensitive to
light intensity