AMITY INTERNATIONAL SCHOOL, NM

CLASS IX

Chapter - 2 – Is Matter around us pure

LAB ACTIVITY HANDOUT-18th July

To Prepare a True Solution, a Colloidal Solution and a

Suspension and distinction between them

Aim

The experiment aims to prepare a true solution of common salt and water,
a colloidal solution of starch and water, a suspension of chalk powder and
water and then distinguish between them based on their appearance, i.e.,
transparency, filtration criterion, and stability.

Theory

Properties of True Solution, Colloidal solution and Suspension

S.no True Solution Colloidal solution Suspension

1 A true solution is a Although the solution It is a mixture that

mixture of solute and is heterogeneous, it is heterogeneous

solvent that is appears to be and is opaque in

homogenous. homogeneous. nature.

2 Solute particles are Solute particles Particles with a

less than 1 nm (1 nm range in size from 1 diameter greater

=10-9m). nm to 1000 nm. (10- than 1000 nm (10-

9
– 10-6 m) 6
m) can be seen

with the naked

eye.
3 The particles do not The particles scatter The suspension

scatter light and do light and produce the particles scatter a

not exhibit the Tyndall effect. beam of light in

Tyndall effect. their suspended

state, which is

known as the

Tyndall effect.

4 The solution is stable The only way to It’s in a state of

(remains uniform). separate the instability.

particles is to use

centrifugation.

5 Filtration will not be The solution is Filtration could be

able to separate the constant. used to separate

particles. the particles.

Material Required

The apparatus and materials required for this experiment are as follows:

Beakers, 3 Test tubes, Common Salt, Chalk powder, Starch powder, Glass

Rod, Water, funnel, filter papers.

Procedure:

Step 1: Fill three beakers with 100 mL of water and label them A, B, and
C, respectively.

Step 2: In each beaker, 10g of common salt (NaCl), starch powder and
fine chalk powder are added separately.

Step 3: Using the glass rod, stir the solution and place the solutions in
test tubes and mark them with the letters A, B, and C respectively.
Step 4: The transparency of each test tube with contents are checked
and observation recorded.

Step 5: Shake the solutions in the test tubes and then allow them to
stand for 20-25 min without disturbing. Then observe.

Step 6: Filter each test tube content using a funnel, filter paper and
stirring rod and observe the filtrate and the residue obtained.

Observation and Inference

S. No. Test tube A Test tube B Test tube C

The solution has

A true solution is a translucent A suspension is
Appearance transparent appearance. opaque in nature.

There is no There is residue of

residue on the wet chalk powder on
filter paper, and the filter paper, and
the filtrate is The resulting the filtrate is clear.
clear. Filtration filtrate is Filtration can
cannot separate translucent. separate the
solid particles There was no suspended
Filtration from true residue on the components of a
Criterion solution. filter paper. suspension.

True solutions are

stable and do not The suspensions are
exhibit not stable and
component No change has contain heavy
deposition even been observed components that
after standing for in test tube B on settle at the bottom
Stability 20-25 min. standing. of the beaker

Precautions

(i) Handle the materials and solutions with care.

(ii) While filtering a solution, pour the contents into the funnel using a
glass rod.

(iii) Do not disturb the sample during the stability test.

Conclusion

Test tube A contains a true solution, test tube B contains a colloidal

solution and test tube C contains a suspension at the end of the

experiment.