Hello Friends, I have made this PPT especially for 10th Standard students of Maharashtra State Board (SSC). This PPT is made highly informative and illustrative, so that each and everyone of you can understand the basics of Science. Best of Luck!

1. UNDERSTANDING
-BY FURQAAN

3. WHAT IS AN ELEMENT?
An element is a substance that is
made entirely from one type of atom.
For example, the element hydrogen is
made from atoms containing a
single proton and a single electron. If
you change the number of protons an
atom has, you change the type of
element it is.

4. Its CLASSIFICATION
ELEMENTS
THEY ARE FURTHER CLASSIFIED
INTO
METALS
NON-
METALS
METALLOIDS

5. WHAT ARE COMPOUNDS?
Compounds are pure substances and not mixtures.
For example, table salt is not a compound because
it is a mixture of sodium chloride, dextrose and
calcium silicate (to keep it from clumping in high
humidity) and potassium iodide (an important
nutrient necessary for proper thyroid function). But
if these components are separated physically, each
can be obtained in pure form and each meets all
the criteria for compounds.

6. Compounds are made of atoms of two or more
elements. For example, O2 and O3are considered
forms of the element oxygen, and not compounds
of oxygen.
Atoms of elements combine in fixed ratios to form
compounds. Carbon dioxide is always composed of
molecules with two atoms of oxygen for every one
atom of carbon. Carbon monoxide has only one
oxygen atom per atom of carbon- and it is a
completely different substance than carbon
monoxide.

7. Compounds are chemically combined
elements. Mixing 2.0 grams of H2 with 70.9 g of
Cl2 in the dark results in a homogenous mixture of
H2 and Cl2. Mix the gases in the exact same
proportions in the light and there is a violent
explosion. The gas is now 72.9 g of HCl, a
compound. Components in a homogenous mixture
may influence each other's chemical behavior
slightly, but there is not radical alteration in
chemical and physical properties. Compounds are
completely different chemically and physically from
the elements that form them.

8. WHAT ARE MIXTURES?
A Mixture is a substance which is obtained by
mixing two or more substances in any proportion.
There are an infinite number of mixtures.
Anything you can combine is a mixture.
Think of everything you eat. Just think
about how many cakes there are. Each of
those cakes is made up of a different
mixture of ingredients. Even the wood in
your pencil is considered a mixture. There
is the basic cellulose of the wood, but there
are also thousands of other compounds in
that pencil. Solutions are also mixtures,
but all of the molecules are evenly spread
out through the system. They are
called homogenous mixtures.

9. The constituents of a mixture retain their original
properties.The mixture can be further subdivided
into simpler substances by simple physical
processes like holding the magnet,hand picking
etc.In a mixture, the constituents are not in a fixed
proportion.When two or more metals or a metal
and a non-metal are fused together then,it is an
alloy.
Stainless Steel is an alloy of iron,carbon,chromium
and nickel. Carbon gives hardness to the mixture.
Chromium and Nickel give a silvery look to the
mixture.

10. TYPES OF MIXTURES
The two types of mixtures are homogeneous and
heterogeneous.
• Homogeneous Mixture : A homogeneous mixture has the
same uniform appearance and composition throughout.
Many homogeneous mixtures are commonly referred to as
solutions. Particle size distinguishes homogeneous solutions
from other heterogeneous mixtures. Solutions have particles
which are the size of atoms or molecules - too small to be
seen.

11. • Heterogeneous Mixture: A heterogeneous mixture
consists of visibly different substances or phases.
The three phases or states of matter are gas, liquid,
and solid.

12. WHAT IS A SOLUTION?
A Solution is a homogeneous mixture of two or
more substances.Lemonade, soda water are
some examples of solutions.
Lemonade or sodas taste the same throughout.It
indicates that there is homogeneity at the
particle level.The particles of sugar or salt are
spread uniformly in the solutions.
There are solid solutions (alloys) and gaseous
solutions (air) also.The particles in a solution
are of very small size, they do not scatter a
beam of light passing through it.

13. Here are types of solutions and some
of their examples:-

14. WHAT IS A SUSPENSION?
A Suspension is a
heterogeneous mixture in
which the solute particles do
not dissolve but remain
suspended in it.These particles
are visible to the naked eye.

15. WHAT IS A COLLOID?
Science has special names for everything.
There are names for the different types of
homogenous mixtures. Solutions refer to
these mixtures when the particles are very
small. You may hear about colloids. Colloids
are just solutions with much bigger
particles.It is a mixture in which the size of
particles is less than the size of particles in
a suspension.

16. Colloids are usually foggy or
milky when you look at them.
In fact, milk is an emulsified
colloid. You may also hear
about colloids if you study
soil. Milk is an organic colloid,
while soils can be made up of
inorganic colloids, such as
clay.
EMULSIFIED:
To make into or form an any colloidal
suspension of a liquid in another liquid.
These particles are spread uniformly throughout the solution
and due to the relatively smaller size of these particles,as
compared to that of a suspension,this mixture appears to be
homogeneous.But a colloid solution is a heterogeneous
mixture.

17. TWO COMPONENTS OF COLLOIDS
The Dispersed Phase and Dispersion Medium are the components.For
eg: milk (Here milk is the Dispersed Phase and water is the Dispersion
Medium) here both the Dispersed Phase and Dispersion Medium are
liquids.We cannot see colloidal particles with the naked eyes.These small
particles can easily scatter the beam of light.
Take a look at this:

18. THE TYNDALL EFFECT
The Tyndall effect, also known as Tyndall
scattering, is light scattering by particles in
a colloid or particles in a fine suspension. It is
named after the 19th century physicist John
Tyndall. It is similar to Rayleigh scattering, in that
the intensity of the scattered light depends on the
fourth power of the frequency, so blue light is
scattered much more strongly than red light. An
example in everyday life is the blue colour
sometimes seen in the smoke emitted
by motorcycles.

19. Some examples of Tyndall Effect:
The Tyndall Effect was discovered by John Tyndall:

20. SEPERATING COMPONENTS OF A MIXTURE
Heterogeneous mixtures can be easily separated by
simple means like hand picking, filtration and other
physical means. Evaporation is another technique
used for separating mixtures. For some mixtures,
one needs techniques like distillation and
crystallization to separate them. Fractional
Distillation is another method where a mixture of
liquids is separated into components according to
their different boiling points. This method is used to
separate components of Air.

22. ALWAYS
REMEMBER