This will give you a complete idea about this topic " is matter around us pure. It is the concept from ncert class9 and it is also useful for ntse level 1 exam

1. IS MATTER AROUND US PURE?

3. Pure Substances:
Pure substances are those which contain only one
kind of particles.
Example:
Hydrogen,
Carbon,
Water,
Carbondioxide,
NaCl..etc

4. ELEMENT
An Element is a pure substance, Which can not be broken
into a simpler substances by any physical or chemical
reaction.
Examples:
Hydrogen, Oxygen, Nitrogen,
Sulphur, Carbon etc.

5. Compound:
A compound is a pure substance, which is composed of
two or more elements, combines chemically in a fixed
proportion by weight, and can be broken into smaller
parts or elements by chemical methodsonly.
Examples:
Sodium
Chloride,
Water,
Ammoniumchloride

7. Differences between Elements and Compounds:
ELEMENTS COMPOUNDS
An Element is made up of
only one kind of atoms
ACompound is made up of
more than one kind of atoms
Thesmallest particle that
retains all its properties is an
atom.
Thesmallest proporties that
retains all its properties is the
molecule.
An Element cannot be broken
into asimplersubstances.
ACompound can be broken
into Elements by a Chemical

8. MIXTURE
Whentwo or more substances mixed together
physically in any proportion is called mixture

9. Mixtures areclassified into two types
1)Homogenous Mixture
2)Heterogeneous Mixture

10. Homogenous Mixture:
A mixturein which differentconstituents are
mixeduniformlyis called homogeneous
mixture.
Example:
Air,Alloys,sugar solution, saltsolution,
Mixture of Alcohol andwater,
Mixture of vinegar andwater,
Blood,
Milk....Etc

11. Heterogeneous mixture:
A mixturein whichvarious constituents are not
mixeduniformlyis called heterogeneousmixture.
Example:
Sand+water,
Oil+water,
Iron+Sulphur,
Rice and
stones,
Pizza.....Etc.

13. Difference between Compoundand Mixture.
MIXTURE COMPOUND
It contains two or moreSubstances It is a single substance
The constituents may be present inany
proportions
The constituents are present indefinite
proportion
Mixtires may be homogenousor
Heterogeneous
Compounds are alwaysHomogenous
The constituents of the mixtureretains
their individual properties
The properties of a compound is
completely defferent from the
properties of its Constituents.

14. SEPARATION OF MIXTURES

16. SUBLIMATION
A Solid state of matter directly changes to
gaseous state without moving to the
intermediate liquid state is called Sublimation
Examples:
Camphor,
Ammonium
Chloride,
Naphthelein,
Iodine

18. CENTRIFUGATION
By Using centrifugation, We separatesolid- liquid
mixture where as the solid particles neither dissolve
nor settleddown
Examples:
Milk,
Blood.

20. SOLVENT EXTRACTION
Solvent extraction is
also called as Liquid-
Liquid Extraction.
This is a method to
separate Compound
based on their relative
solubilities in two
immiscible
liquids.

21. SIMPLE DISTILLATION
Distillation is a process of obtainingpure
liquid froma solution
Distillation = Evaporation + Condensation

23. FRACTIONAL DISTILLATION
Fractional
distillation is a
method for
separating
liquids with
differentboiling
points

24. Fractional
distillation is
used in
petrochemical
industry to
obtain different
fractions of
petroleum

25. SEPARATION OF GASES FROM
AIR
Air is a
homogeneous
mixture and can
be separatedinto
its components
by fractional
distillation

27. Adsorption
Adsorption is the
process in which
the particles of a
substance is
concentrated only at
the surface
of another substance.

28. Absorption is the
process in which
the substance is
uniformly
distributed throughout
the bulk of
another substance.
Absorption

29. Chromatography
Chromatography is also a
separation technique. It is used to
separate different components of a
mixture based on their different
solubilities in the same solvent

30. Paper Chromatography

31. Crystallization
crystallisation is the process by which
a solid forms, where the atoms or
molecules are highly organized into a
structure known as a crystal.

33. Solutions
A solution is a homogeneous mixture of
two or more substances.
Solvent: the component present in larger
amount by weight is called solvent.
Solute:the component present in lesser
amount by weight is called solute.

34. Types of Solutions
1. Based on Size of particle
Based on the particle size of the substance, the solutions are
divided into three types.

35. Colloidal Solutions:
A colloidal solution is a heterogeneous system
consisting of the dispersed phase and the dispersion
medium. Dispersed phase or the dispersion medium
can be a solid, or liquid or gas.
Dispersed phase
The phase that is scattered or present in the form of colloidal
particles is called the dispersed phase
Dispersion medium
The medium in which the colloidal particles are dispersed is
called the dispersion medium.

36. Example:
• In a starch solution, starch represents the dispersed
phase, while water represents the dispersion medium.
• In milk, Fat is the dispersed phase and water is
the dispersion medium.
• In blood dispersed phase is hormones, Respiratory
gases, RBC, WBC, Platelets, proteins,Digested food
etc. while the dispersed medium is Plasma

37. Classification of Colloids

38. Brownian Movement
When colloidal solution are viewed
under powerful microscope, it can
be seen that colloidal particles are
moving constantly and rapidly in
zig-zag directions. The Brownian
movement of particles is due to
the unbalanced bombardment of
the particles by the molecules of
dispersion medium.

39. Tyndall effect
When a strong beam of light is focused on a colloidal
solution the path of the beam becomes visible. This
phenomenon is known as Tyndall effect.
The illuminated
path is called
Tyndall cone.

41. Emulsions
• An emulsion is a special type of mixture
made by combining two liquids that
normally don’t mix.
• An emulsion is a colloid of two or more
immiscible liquids where one liquid is
dispersed in another liquid.

42. Examples:
• Oil and water mixtures are emulsions when
shaken together. The oil will form drops and
disperse throughout the water
• Egg yolk is an emulsion containing the
emulsifying agent lecithin.
• Mayonnaise is an oil in water emulsion that
is stabilized by the lecithin in egg yolk.

43. Types of Emulsions
Oil in Water (O/W)
Oil in Water emulsion system is a system where the
oil is dispersed throughout the aqueous phase.
Ex: Milk
Water in Oil emulsion system is a system where the
water is dispersed throughout the oil.
Ex: Butter
Water in Oil (W/O)

44. Difference between Physical and Chemical changes