To prepare true solutions, suspensions and colloidal solutions - Lab Experiment, Class 9 Science Video Lecture

to prepare a true solution of common
salt sugar and alum a suspension of soil
chalk powder and fine sand and water a
colloidal solution of starch and egg
albumen in water and distinguish between
these on the basis of transparency
filtration stability a true solution is
a homogeneous transparent solution in
which solute completely dissolves in the
solvent and cannot be separated from
solvent by filtration it has a particle
size is less than 10 raised to the power
minus 9 meter it is a clear and
transparent solution passes through the
filter paper easily is stable and does
not scatter light a colloidal solution
is a heterogeneous mixture anis
translucent it has a particle size which
ranges between 10 raised to the power
minus 8 meter to 10 raised to the power
minus 6 meter it can pass through filter
paper and is stable a suspension is a
heterogeneous opaque mixture particle
size of suspension is more than 10
raised to the power minus 5 meter its
particles do not pass through filter
paper and settle under gravity when left
undisturbed for some time model how can
we distinguish between these we can
distinguish these on the basis of
transparency filtration and stability
let's do an experiment to distinguish
true suspension and colloidal solution
our aim here is to prepare a true
solution of common salt sugar an alum a
suspension of soil chalk powder and fine
sand in water a colloidal solution of
starch and egg albumin in water and
distinguish between these on the basis
of transparency filtration stability the
materials required are test tubes
beakers water almond salt sugar alum
soil chalk powder fine sand egg albumen
starch funnel glass rod and filter paper
procedure preparation of solutions or
mixtures take 8 beakers and label them
as a b c d e f g h and add 50 ml of
water to each beaker add samples of any
c l sugar and alum to beakers a b and c
stir to make clear solutions add soil
chalk powder and fine sand to beakers d
e and f stir for some time add a small
amount of starch to water and boil the
content in beaker g in be courage add
egg albumin and stir vigorously this
should not be heated
observe the mixtures and record the
observations observations beakers ABC
transparency the solutions are clear and
transparent and particles are not
visible stability the particles do not
settle down as sediments the solutions
are therefore stable filtration salt
solution can easily pass through filter
paper and no residue is seen on filter
paper type of solutions solutions ABC
are true solutions beakers bef
transparency solutions are opaque the
particles are visible with naked eyes
and labels are not visible from the
other side stability the particles
settle down on standing undisturbed and
the solutions are therefore unstable
filtration the particles do not pass
through filter paper and residue is seen
on filter paper type of solutions
solutions d EF our suspension solutions
beakers gh transparency the solutions
are turbid but the particles are not
visible the labels are dimly visible and
solutions are translucent stability the
particles do not settle down our
sediments the solutions are therefore
stable filtration the particles pass
through filter paper and no residue is
seen on
filter paper type of solutions
pollutions G and H are colloidal
solutions result beaker a common salt
forms true solution and water beaker be
sugar forms a true solution in water
beakers see alum forms a true solution
in water
beaker D soil forms a suspension in
water beaker e chalk powder forms a
suspension in water beaker F finds and
forms a suspension in water beaker G
starch forms a colloidal solution in
water beaker H egg albumin forms a
colloidal solution in water precautions
distilled water should be used the
components should be mixed in small
amounts fold the filter paper properly
and moisten it before use glass rod
should be clean shake the contents of
solution or suspension or colloid
thoroughly in water
thank you mom we have understood the
experiment very well