Birla Public School, Doha- Qatar
Science- Chemistry.
Class IX:
Ch- 2- Is Matter around us pure- Notes
Introduction
Matter
Anything which has mass and occupies space is called matter. It may be solid, liquid or
gas.
Substance: - It is a kind of matter that cannot be separated into other kinds of matter by
any physical methods. Eg: Salt, Sugar, Water soil, alloy etc.
The properties of substance can be divided as physical property and chemical
property.
The properties that can be observed and specified are physical properties. Eg: colour,
hardness, rigidity, density, melting point, boiling point, etc.
The chemical property is a characteristic of a substance that may be observed when it
participates in a chemical reaction.
The substance can undergo a physical change and a chemical change.
Difference between Physical and Chemical changes:
https://youtu.be/evcnb7KDUak, https://youtu.be/LZH8DzQTsQY
S.
No.
Physical Change
chemical change (Chemical
reaction)
1.
Here only the physical
properties like state, shape or
size of a substance change.
It brings about a change in the
chemical properties of a
substance.
2.
There is no change in chemical
composition of a substance.
There is always a change in
chemical
composition of a substance.
3.
No new substance is formed.
A new substance is always
formed.
4.
It is temporary and hence
reversible.
It is permanent and hence
irreversible.
5.
Eg. Melting of ice, dissolving
sugar in water
Eg. Burning of paper, rusting of
iron.
Types of substance:
It is of two types:
1. Pure Substance
2. Impure substance
1. Pure Substance: It may be defined as a material which contains only one kind of
particles.
Pure substances are again of two types:
(a) Elements (b) Compounds
(a) Elements:
* Robert Boyle used the term element for the first time.
* Lavoisier gave definition of element as follows:An element is a basic form of matter that cannot be broken down into simpler
substances by chemical reactions.
Pure substances which are made up of only one kind of particles are known as
elements.
They cannot be split up into two or more simpler substances by any of the usual
chemical methods.
For example: Iron, gold, silver, carbon, oxygen, nitrogen and sodium etc.
Elements are further grouped into the following three categories:
(i) Metals:- The elements that are generally solid, lustrous, sonorous, malleable,
ductile, strong and hard, denser, conductors of heat and electricity etc are called
metals. (The definition is based on physical properties). Example: Iron, copper, gold,
sodium, silver, mercury, etc.
(ii) Non – metals:- The elements that are generally opposite to metals in the physical
properties are called non- metals. Example: Carbon, oxygen, sulphur, nitrogen, oxygen,
hydrogen, etc.
(iii) Metalloids:- The elements that have intermediate properties between those of
metals and non- metals are called metalloids. Eg: Boron, silicon, germanium, Arsenic,
Tellurium etc.
Physical Properties of Metals:

These are lustrous (shine).

They conduct heat and electricity.

All metals are malleable and ductile.

They are sonorous.


All metals are hard except sodium and potassium.
All metals are solids at room temperature except mercury which is a liquid.
Physical Properties of Non-metals:

These are dull in appearance.

They are poor conductors of heat and electricity except diamond which is a good
conductor of heat and graphite which is a good conductor of electricity.

They are neither malleable nor ductile.

They are generally soft except diamond which is the hardest natural substance known.

They may be solids, liquids or gases at room temperature.
Metalloids: The elements that have properties intermediate between those of metals
and non-metals, are called metalloids.
(b) Compounds:

It is a form of matter formed by combining two or more elements in a definite ratio by
mass and they are formed by chemical combination.

It can be decomposed into its constituent elements by suitable chemical methods
For example: Water (H2O), oxygen (O2), Nitrogen dioxide (NO2), etc.
Illustrate that water and carbon dioxide are compounds.
Water: Water is a compound formed by combining Hydrogen and Oxygen chemically
and it has a chemical formula, H2O. In a water particle, 2 atoms of Hydrogen and 1
atom of Oxygen are present. When we consider the mass ratio of Hydrogen and
Oxygen in one particle of water, it comes as follows:
Mass ratio of Hydrogen and Oxygen in water
= 2 X mass of 1 atom of H : 1 X mass of 1 atom of O
= (2 X 1u) : (1 X 16u) = 2 : 16 = 1: 8
Whatever be the source of water this mass ratio remains a constant. So, Water is a
compound.
Carbon dioxide: Carbon dioxide is a compound formed by combining Carbon and
Oxygen chemically and it has a chemical formula, CO2. In a carbon dioxide particle,
1atom of Carbon and 2 atoms of Oxygen are present. When we consider the mass ratio
of Carbon and Oxygen in one particle of carbon dioxide, it comes as follows:
Mass ratio of Carbon and Oxygen in carbon dioxide
= 1 X mass of 1 atom of C : 2 X mass of 1 atom of O
= (1 X 12u) : (2 X 16u) = 12 : 32 = 3 : 8
Whatever be the source of carbon dioxide this mass ratio remains a constant. So,
Carbon dioxide is a compound.
2. Impure Substance: It may be defined as a material which contains more than one
kind of pure substances. It is also named as mixture.
Mixtures:
A mixture is a material which contains two or more different kinds of particles (atoms or
molecules) which do not react chemically but are physically mixed together in any
proportion.
https://youtu.be/t0iHbY9sjDc
https://youtu.be/XEAiLm2zuvc
Activity 2.10- text book page number 25 (Refer Text book) - Activity to distinguish
mixture and compound. https://youtu.be/C2RqAE0wbqk
Activity:- Group I- Mix and Iron and Sulphur Powders manually
Group II- Mixture of Iron and Sulphur Powder is taken in a china dish and
heated strongly till red hot and cool it.
Both the groups conducted the following tests on the substances with them.
Activity
Observation done by
Observation done by
group-I
group-II
Appearance- colour and
Non- uniform, yellow
Uniform, only black colour
texture
colour of Sulphur and
is observed.
greyish colour of Iron are
observed
Test with magnet
Iron powder got attracted
Nothing got attracted
to magnet
Dissolution in carbon
Sulphur dissolved, but not
Nothing dissolved
disulphide
iron
Heating with dilute
A colourless, odourless
A colourless gas with
hydrochloric acid or
gas is evolved. On testing
rotten egg’s smell is
sulphuric acid
the gas with a burning
evolved. On passing the
match stick, the stick
gas through blue coloured
extinguished with a ‘pop’
copper sulphate solution,
sound and the gas is
the colour of the solution
combustible. So, it is
turned into black. So, the
hydrogen gas.
gas is hydrogen sulphide.
Conclusion: The differences in the observations of the same activities showed that
group I obtained a mixture and group II obtained a compound. The compound they
obtained is iron sulphide.
Difference between mixtures and compounds:
S.
No.
Mixtures
Compounds
1.
Various elements just mix
together to form a mixture and
no new compound is formed.
Elements react to form new
compounds.
2.
A mixture has a variable
composition.
The compound has a fixed
composition.
3.
A mixture shows the properties
of its constituents.
Properties of a compound are
totally different from those of its
constituents.
4.
They do not have a fixed
melting point, boiling point, etc.
They have a fixed melting point,
boiling point, etc.
5.
The constituents can be
separated easily by physical
methods
The constituents can be separated
only by chemical processes.
Types of mixture
It is of two types:
(a) Homogeneous mixture
S.
No.
(b) Heterogeneous mixture
Homogeneous mixture
Heterogeneous mixture
1.
All the components of the
mixture are uniformly mixed.
All the components of the mixture
are not thoroughly mixed.
2.
No separation boundaries are
visible.
Separation boundaries are visible.
3.
It consists of a single phase.
It consists of two or more phases.
4.
Example: Sugar dissolved in
water, Salt solution, Vinegar,
Air.
Example: sand and common salt
mixture, Soil
5.
It is also called solution
It can be suspension and colloid.
Try the following questions:
Q1. Is air around us a compound or a mixture?
Q2. Water is a compound. Justify.
Q3. Differentiate between homogeneous and heterogeneous mixtures.
Q4. Give reasons for the following:
(a) Copper is used for making electric wires.
electrode in a dry cell.
(b) Graphite is used for making
Q5. List any four characteristics by which compounds can be differentiated from
mixtures.
Homogeneous mixture- Solution
A solution is a homogeneous mixture of two or more substances. For example: Lemon
water, sugar solution, soda water, etc.
Components of Solution:
(1) Solvent: The component of the solution that dissolves the other component in it and
is usually present in larger amount, such component of solution is called the solvent.
For example: Water, alcohol etc.
(2) Solute: The component of the solution that is dissolved in the solvent and is usually
present in lesser quantity, such component is called the solute. For example: Salt,
sugar, iodine etc.
Properties of solutions:
(i) It is a homogeneous mixture.
(ii) Particle size in a solution is less than 1 nm in diameter.
(iii) Particles of a solution cannot be seen even with a microscope.
(iv) A true solution does not scatter the light; ie, it does not show Tyndall effect. The
scattering of light by the particles of a medium is called Tyndall effect.
(v) Solution is stable.
(vi) The solute particles cannot be separated from the mixture by the process of
filtration.
Types of solutions: a) Based on physical state of components (solute & solvent)
Various types of solutions are:
(i) Solid in a solid solution: Alloys.
(ii) Solid in a liquid solution: Sugar solution, salt solution.
(iii) Liquid sin a liquid solution: Lemon water, vinegar (acetic acid in water)
(iv) Gas in a gas solution: Air.
(v) Gas in a liquid solution: Soda water.
Alloys: They are a homogeneous mixture of two or metals or a metal and a non- metal
which cannot be separated into their components by physical methods. But still, an alloy
is considered to be a mixture because it shows the properties of its components and
can have variable composition. Eg: Brass is an alloy of 30% Zinc and 70% Copper.
Bronze is an alloy of 88% copper and 12% tin.
b) Based on the type of solvent:- i) Aqueous solution:- When water is used as the
solvent in a solution, it is called aqueous solution. Because of its easy availability,
physical state of liquid at room temperature, ease of handling and ability to dissolve
many substances, water is regarded as ‘Universal Solvent’.
ii) Non- Aqueous solution:- When solvents other than water are used as solvent to
prepare a solution, it is called non- aqueous solution. Eg for non-aqueous solvents:
Carbon tetra chloride, alcohol, carbon disulphide, chloroform etc.
c) Based on amount of component- solute
The term concentration is used to refer the amount of solute present in a solution. If the
solution has less amount of solute it is said to be of low concentration or dilute
solution. If a solution has more amount of solute, it is said to be of high concentration
or concentrated solution.
Concentration of a solution: It is defined as the amount of solute present in a
given quantity of a solution. OR
It is defined as the mass of the solute in grams present in 100 grams of the solution.
Concentration of a solution can be calculated by percentage method which expresses
the concentration or percentage of solute in the solution. The percentage of solute can
be mass by mass percentage, mass by volume percentage or volume by volume
percentage.
If a solution is of a solid in liquid type, we take mass by mass or mass by volume
percentage. If the solution is of liquid in liquid, we consider volume by volume
percentage for concentration. We can use the following formula for this;
𝑪𝒐𝒏𝒄𝒆𝒏𝒕𝒓𝒂𝒕𝒊𝒐𝒏 𝒐𝒇 𝒔𝒐𝒍𝒖𝒕𝒊𝒐𝒏 =
𝑨𝒎𝒐𝒖𝒏𝒕 𝒐𝒇 𝒔𝒐𝒍𝒖𝒕𝒆
𝑨𝒎𝒐𝒖𝒏𝒕 𝒐𝒇 𝒔𝒐𝒍𝒖𝒕𝒊𝒐𝒏
In percentage method: Mathematical expression for concentration of solution:
i) 𝑴𝒂𝒔𝒔 𝒃𝒚 𝒎𝒂𝒔𝒔 % 𝒐𝒇 𝒂 𝒔𝒐𝒍𝒖𝒕𝒊𝒐𝒏 =
𝑴𝒂𝒔𝒔 𝒐𝒇 𝒔𝒐𝒍𝒖𝒕𝒆
𝑴𝒂𝒔𝒔 𝒐𝒇 𝒔𝒐𝒍𝒖𝒕𝒊𝒐𝒏
ii) 𝑴𝒂𝒔𝒔 𝒃𝒚 𝒗𝒐𝒍𝒖𝒎𝒆 % 𝒐𝒇 𝒂 𝒔𝒐𝒍𝒖𝒕𝒊𝒐𝒏 =
× 𝟏𝟎𝟎
𝑴𝒂𝒔𝒔 𝒐𝒇 𝒔𝒐𝒍𝒖𝒕𝒆
𝑽𝒐𝒍𝒖𝒎𝒆 𝒐𝒇 𝒔𝒐𝒍𝒖𝒕𝒊𝒐𝒏
× 𝟏𝟎𝟎
In case of liquid solute in liquid solvent concentration can be expressed as:
iii) 𝑽𝒐𝒍𝒖𝒎𝒆 𝒃𝒚 𝒗𝒐𝒍𝒖𝒎𝒆 % 𝒐𝒇 𝒂 𝒔𝒐𝒍𝒖𝒕𝒊𝒐𝒏 =
𝑽𝒐𝒍𝒖𝒎𝒆 𝒐𝒇 𝒔𝒐𝒍𝒖𝒕𝒆
𝑽𝒐𝒍𝒖𝒎𝒆 𝒐𝒇 𝒔𝒐𝒍𝒖𝒕𝒊𝒐𝒏
× 𝟏𝟎𝟎
Mass of solution = Mass of solute + mass of solvent
(Numerical from text book and extra questions)
d) Based on solubility of solute
Solubility:
The maximum amount of the solute which can be dissolved in 100 grams of a solvent at
a particular temperature is known as its solubility in that particular solvent. Or
The amount of the solute present in the saturated solution at a given temperature.
Different solutes have different solubility in a solvent. Eg: The solubility of Potassium
nitrate in 100 grams of water at 200C is 32 g whereas the solubility of Sodium chloride in
100 g of water at 200C is 36g.
Conditions or factors affecting solubility:
(i) Temperature: Solubility of solids in liquids increases with the increase in
temperature, whereas solubility of gases in liquids decreases on increasing the
temperature.
(ii) Pressure: Solubility of gases in liquids increases on increasing the pressure,
whereas the solubility of solids in liquids remains unaffected by the change in pressure.
Based on solubility of solute, Solution can be divided as
Saturated Solution: A solution in which no more quantity of solute can be dissolved at
a particular temperature, is called saturated solution.
Unsaturated Solution: A solution in which more quantity of solute can be dissolved
without raising its temperature, is called unsaturated solution.
Super saturated solution:- A solution which contains solute more than the saturation
level is called super saturated solution.
Try the following questions:
Q1. What would it mean by saying a 15% of alcohol solution?
Q2. Calculate the concentration of a solution containing 2.5g of salt dissolved in 50g of
water.
Q3. Name the different types of solutions along with an example for each.
Q4. Define (a) Solute (b) Solvent.
Heterogeneous mixture- a) Colloid
A heterogeneous mixture which appears to be uniform (homogeneous) due to the
relative smaller size of the particles and it can scatter a beam of light is called a colloid.
OR
Solutions in which the size of particles lies in between those of true solutions and
suspensions are called colloidal solutions or simply colloids. For example: Milk, smoke
and starch solution etc.
Properties: (i) It is a heterogeneous mixture.
(ii) Particle size in a colloid is between 1 nm- 100nm in diameter.
(iii) Particles of a colloid cannot be seen even with naked eye.
(iv) A colloid can scatter the light; ie, it shows Tyndall effect.
(v) Colloid is stable.
(vi) The particles cannot be separated from the mixture by the process of filtration.
Components of a colloid: i) Dispersed phase- The solute like component or the
dispersed particles in a colloid is called dispersed phase.
ii) Dispersing medium- the solvent like component or the component in which the
dispersed phase is suspended is called dispersing medium
Tyndall Effect: The scattering of light by the colloidal particles is known as Tyndall
effect.
It can be observed when:


A fine beam of light enters a room through a small hole.
Sunlight passes through the canopy of a dense forest.
Note: The colloidal particles are not the true solutions as their particles are
big enough to show the Tyndall effect, whereas the particles of a true
solution do no show Tyndall effect.
https://youtu.be/W4KAbbVNMxc
Types of colloid- Based on the physical state of the components of a colloid.
Dispersed Dispersing Type of colloid
Example
phase
medium
Liquid
Gas
Aerosol
Fog, cloud, mist
Solid
Gas
Aerosol
Smoke, automobile exhaust
Gas
Liquid
Foam
Shaving cream
Liquid
Liquid
Emulsion
Milk, face cream
Solid
Liquid
Sol
Milk of magnesia, mud
Gas
Solid
Foam
Foam, rubber, sponge, pumice
Liquid
Solid
Gel
Jelly, cheese, butter
Solid
Solid
Solid Sol
Coloured gemstone, milky glass
Heterogeneous mixture- b) Suspension
A heterogeneous mixture in which the solute particles do not dissolve but remain
suspended throughout the bulk of the medium and are visible to naked eye is called a
suspension. Eg: muddy water, chalk powder in water, flour in water, etc.
OR
The heterogeneous mixture in which solids are dispersed in a liquid are called
suspensions.
Properties of a Suspension:
(i) It is a heterogeneous mixture.
(ii) The particles of a suspension can be seen by naked eyes.
(iii) The particles of a suspension scatter a beam of light passing through it and make its
path visible.
(iv) A suspension is unstable.
(v) Constituents of a suspension can be separated by the process of filtration.
Differences between solution, colloid and suspension
Property
Solution
Colloid
Suspension
Homogeneity
(uniformity)
Homogeneous
Appears to be
homogeneous, but
Heterogeneous
Heterogeneous
Particle size
Lesser than 1 nm
1 nm- 100 nm
Greater than 100 nm
Stability
(settlement of
particles)
Stable since
particles do not
settle down
Stable
Unstable since particles
can settle down
Filterability
Cannot filter
Cannot filter
Can be filter
Tyndall effect
Do not show
Shows
Shows before the
settlement of particles.
Transparency
Transparent
Translucent
Opaque
Try the following questions:
Q1. How will you distinguish a colloid from a solution?
Q2. What is effect of temperature on the solubility of solids in liquids?
Q3. Sea water can be classified both as a homogeneous as well as a heterogeneous
mixture. Comment?
Q4. Distinguish between the following as physical changes and chemical changes?
(a) Burning of a magnesium wire
(b) Rusting of iron
(c) Condensation of steam
(d) Glowing of an electric bulb
The separation of components of a Mixture:
Need of separation of components of a mixture:
To remove the unwanted substances
To obtain the useful substances
To get the pure substances
To get individual components and study and use them.
Some of the important methods used to separate different mixtures are explained
below:
(1) Filtration: - The process of separating an insoluble solid from a liquid by using a
filter or filter paper is called filtration. The principle of this method is solubility.
Application: It is applied in supply of drinking water in cities, towns etc.
The main steps in this are:- a) sedimentation, b) Loading (The process of adding
certain substances like alum to settle the minute suspended solid particles in water), c)
Filtration, d) Chlorination (adding chlorine to destroy germs), e) Supply. Refer Fig. 2.13
in txt bk pg# 24.
(2) Evaporation:
Evaporation is a process which is used to separate a solid substance dissolved in liquid.
It is based on the fact that liquids vaporize easily whereas solids do not. So we can
separate a volatile (vapourising solvent) component from its non- volatile (solute)
component by evaporation. The principle of this method is volatility.
Activity 2.4- Refer Txt Bk Pg # 19 (How can we get coloured component (dye) from
ink?)
Ink is a mixture of a dye in water.
Applications of Evaporation:
Obtaining salt from sea water, Separating dye from ink
(3) Centrifugation:
It is a method of separating the suspended particles of a substance from a liquid in
which the mixture is rotated at high speed in a centrifuge. The principle of this method is
density. It is a better method for separating colloidal mixtures.
This method is useful in case the suspended particles in a liquid are too small to be
retained by filter paper. When the mixture is rotated at high speed, the suspended
particles get collected, becoming heavy and settling down and the lighter particles stay at
the top.
Applications of Centrifugation:


Used in dairies to separate cream from milk.
Used in washing machines to squeeze out water from wet clothes.
(3) Separating funnel
Description of Separating Funnel:- It is a special type of funnel which has a stop
cock or tap on its stem to control the flow of liquid from the funnel. It has a lid at
the top. It is used to separate two immiscible liquids using the principle of
density.
It is used to separate a mixture of two immiscible liquids, like oil and water.
Refer Activity 2.6- Txt bk Pg# 20
https://www.youtube.com/watch?v=7oqLUIHpqOc


Principle of separating funnel:
When a mixture of two immiscible liquids is kept in a separating funnel, the liquids
separate out in layers depending on their densities.
Applications of Separating funnel:
To separate mixture of oil and water.
In the extraction of iron from its ore where the lighter slag (molten waste material) is
removed from the top by to leave the molten iron at the bottom of the blast furnace.
(4) Sublimation:
This method is used to separate those components from a mixture which can sublime
on heating. So, It is a method of separating a sublimable component from a nonsublimable component from their mixture. For example: Ammonium chloride, camphor,
naphthalene etc, can be separated from their mixture by sublimation. Principle of the
method is sublimation.
https://www.youtube.com/watch?v=XqRx3tydnxc


Applications of Sublimation:
Iron can be separated from a mixture of iron fillings and camphor (volatile).
Common salt can be separated from a mixture of salt and ammonium chloride (volatile).
(5) Chromatography
This method is used to separate two or more dissolved solids which are present in a
solution in very small quantities.
https://www.youtube.com/watch?v=1LdYvgy94fg
https://www.youtube.com/watch?v=PvHvx7k7UPU
Activity 2.7- Refer Txt Bk Pg # 21
Principle of Chromatography:
This method of separation is based on the fact that though two substances are
dissolved in the same solvent but their solubilities can be different. The component
which is more soluble in, rises faster and gets separated from the mixture.



Applications of Chromatography:
To separate colours in a dye by paper chromatography.
To separate pigments from natural colours
To separate drugs from blood, also in forensic science to detect and identify the amount
of substance like poison in the body.
(6) Distillation:
This method is used to separate a mixture solid in a liquid. It is the process of heating
the liquid to form vapour, and then cooling the vapour to get back liquid. It is used for
the separation of components of a mixture containing two miscible liquids that boil
without decomposition and have sufficient difference in their boiling points- more than
25K. Activity 2.8- Refer Txt Bk Pg # 21
Description of the apparatus:- The apparatus used for distillation consists of a
distillation flask and a condenser. Distillation flask is a round bottomed flask
having a side tube. The condenser is a long narrow glass tube surrounded by a
wider glass tube called water jacket. The water jacket has inlet to circulate the
cold water and an outlet to take out the hot water.
During distillation, cold water is circulated in the water jacket of the condenser
and condenses the hot vapour passing through the inner tube of the condenser.
So the water becomes warm and can be collected out through the outlet.
https://www.youtube.com/watch?v=V5ep0-ojPGw
Principle of Distillation:
The volatile liquid evaporates on heating which can be recovered by cooling its vapours
by the process of condensation.



Applications of Distillation:
It is used to remove salt from sea water to obtain drinking water.
It is used to prepare distilled water.
It is used to obtain pure solvent from a solution.
(7) Fractional distillation
https://www.youtube.com/watch?v=vRHk4bOivAk
It is the process of separating two or more miscible liquids by distillation, the distillate
being collected in fractions due to boiling at different temperatures.
Fractionating Column:
The apparatus used in this process is similar to that for simple distillation except
a fractionating column which is fitted in between the distillation flask and the
condenser. A simple fractionating column is a tube packed with glass beads. The
beads provide surface for the vapours to cool and condense repeatedly.
Principle of Fractional Distillation:
In a mixture of two or more miscible liquids, the separation of various liquids depends
on their boiling points. The liquid having lower boiling point boils first and can be
obtained first from the fractionating column than the liquid having higher boiling point.



Applications of Fractional Distillation:
It is used to separate a mixture of miscible liquids like alcohol-water mixture.
It is used to separate crude oil ‘petroleum’ into useful fractions like kerosene, petrol,
diesel, etc.
It is used to separate different gases of the air by taking the liquid air.
How can we obtain different gases from air? Refer the flow chart- Fig. 2.11- Txt bk
Pg# 22, Fig. 2.12- Txt bk Pg# 23.
(8) Crystallisation:
Crystallisation is a process used to separates a pure solid in the form of its crystals from
a solution. The process involves cooling a hot, concentrated solution of a substance to
obtain crystals.
How can we obtain pure copper sulphate from impure sample?
Refer Activity 2.8- Refer Txt Bk Pg # 21
Advantages of Crystallisation or merits of Crystallisation over evaporation
This method can be used to separate pure crystals from the impure samples, but in
evaporation, these impurities may remain along with the solid.
This method can be used even for the separation of solids that decompose or get
charred on heating during evaporation



Applications of Crystallisation:
Purification of common salt obtained from sea water.
To obtain crystals of alum (phitkari) from impure samples.
To obtain pure copper sulphate from an impure sample.
Separation of Mixture and Separation Techniques used
Types of Mixture
Separation Technique
Principle
Insoluble solid in a
solvent
Filtration
Particle size
Fine particles of solid
present in the solvent
Centrifugation
Density of
components
Solution of solid in liquid
to get solid
Evaporation
Volatility of
components
Solution of solid in liquid
to get pure solid
Crystallisation
Volatility of
components
Solution of solid in liquid
to get solid as well as
pure liquid
Distillation
Difference in boiling
point
Miscible liquids having
difference in boiling point
more than 250C
Simple distillation
Difference in boiling
point
Miscible liquids having
difference in boiling point
less than 250C
Fractional distillation
Difference in boiling
point
Immiscible liquids
Using a separating funnel
Difference in density
of the liquids
Mixture of two solids in
which one can sublime
Sublimation
Sublimation
Mixture of substances in
solution having different
solubility
Chromatography
Difference in solubility
Mixture of magnetic and
non- magnetic
substances
Magnetic separation
Magnetic property
Try the following questions:
Q1. Name the method of separation that you will apply for separation of the following
mixtures?
(a) Ammonium chloride from a powdered mixture of sodium chloride and Ammonium
chloride.
(b) Butter from cream.
(c) Oil from water.
Q2. Which of the following will show Tyndall effect:
(a) Salt solution
(b) Milk
(c) Starch
Q3. How will you separate a mixture of iron filings, chalk powder and common salt?
Q4. Discuss the process of purification of impure copper sulphate by crystallization.
Q5. Explain how nitrogen, oxygen and argon gases are separated from air?
Prepared by: Sheri Symon