Distinguishing between solutions
True solutions
For the preparation of a true solution of sugar in water:
Add 10g of fine powdered sugar in a 250ml beaker containing 95ml distilled water.
Then stir the solution using a glass rod until the sugar dissolves.
To check the transparency of sugar solution Take some of the sugar solution in a test
tube. Paste a small strip of cellophane paper on one side of the test tube and view it from
the other side. The cellophane paper is clearly seen from the other side of the test tube.
This indicates that a true solution is transparent. To do the filtration of sugar solution
Place a funnel over a test tube using a clamp stand. Then place a filter paper in the funnel.
Now pour some sugar solution taken in another test tube through the funnel. A clear filtrate
is obtained. There is no residue left on the filter paper.
This indicates that solid particles cannot be separated from a true solution by filtration.
To check the stability of sugar solution Take some sugar solution in a test tube and
leave it in a test tube rack for 20 minutes. The solution remains as it is without sediments.
This indicates that true solutions are stable and do not show components deposits.
For the preparation of a true solution of common salt in water:
Add 10g of fine powdered salt in a 250ml beaker containing 95ml distilled water.
Then stir the solution using a glass rod until the salt dissolves.
To check the transparency of salt solution Take some salt solution in a test tube. Paste
a small strip of cellophane paper on one side of the test tube and view it from the other
side. The cellophane paper is clearly seen from the other side of the test tube. This
indicates that a true solution is transparent.
To do the filtration of salt solution
Place a funnel over a test tube using a clamp stand. Then place a filter paper in the funnel.
Now pour some salt solution taken in another test tube through the funnel. A clear filtrate
is obtained. There is no residue left on the filter paper.
This indicates that solid particles cannot be separated from a true solution by filtration.
To check the stability of salt solution Take some salt solution in a test tube and
leave it in a test tube rack for 20 minutes. The solution remains as it is without sediments.
This indicates that true solutions are stable and do not show components deposits.
For the preparation of a true solution of alum in water:
Add 10g of alum in a 250ml beaker containing 95ml distilled water.
Then stir the solution using a glass rod until the alum dissolves.
To check the transparency of alum solution
Take some of the alum solution into a test tube. Paste a small strip of cellophane paper
on one side of the test tube and view it from the other side. The cellophane paper is clearly
seen from the other side of the test tube. This indicates that a true solution is transparent.
To do the filtration of alum solution Place a funnel over a test tube using a clamp
stand. Then place a filter paper in the funnel. Now pour some alum solution taken in another
test tube through the funnel. A clear filtrate is obtained.
There is no residue left on the filter paper. This indicates that solid particles cannot
be separated from a true solution by filtration. To check the stability of alum solution
Take some alum solution in a test tube and leave it in a test tube rack for 20 minutes.
The solution remains as it is without sediments. This indicates that true solutions are stable
and do not show components deposits.
Suspensions
For the preparation of a suspension of soil in water:
Add 10g of fine soil in a 250ml beaker containing 95ml distilled water.
Then stir the solution using a glass rod. To check the transparency of soil solution
Take some of the soil suspension in a test tube. Paste a small strip of cellophane paper
on one side of the test tube and view it from the other side. The cellophane paper is not
visible from the other side of the test tube. This indicates that a suspension is opaque.
To do the filtration of soil solution Place a funnel over a test tube using a clamp
stand. Then place a filter paper in the funnel. Now pour the soil suspension taken in another
test tube through the funnel. A clear filtrate is obtained.
Soil particles are seen on the filter paper. This indicates that suspended components of
a suspension can be separated by filtration. To check the stability of soil solution
Take some soil suspension in a test tube and leave it in a test tube rack for 20 minutes.
You will note a gradual settlement of soil particles at the bottom of the test tube.
This indicates that a suspension is unstable and show settlement of heavier particles.
For the preparation of a suspension of chalk in water:
Add 10g of fine chalk powder in a 250ml beaker containing 95ml distilled water.
Then stir the solution using a glass rod.
To check the transparency of chalk solution
Take some of the chalk suspension in a test tube. Paste a small strip of cellophane paper
on one side of the test tube and view it from the other side. The cellophane paper is not
visible from the other side of the test tube. This indicates that a suspension is opaque.
To do the filtration of chalk solution Place a funnel over a test tube using a clamp
stand. Then place a filter paper in the funnel. Now pour the chalk suspension taken in another
test tube through the funnel. A clear filtrate is obtained.
Chalk particles are seen on the filter paper. This indicates that suspended components of
a suspension can be separated by filtration. To check the stability of chalk solution
Take some chalk suspension in a test tube and leave it in a test tube rack for 20 minutes.
You will note a gradual settlement of soil particles at the bottom of the test tube.
This indicates that a suspension is unstable and show settlement of heavier particles.
For the preparation of a suspension of fine sand in water:
Add 10g of fine sand in a 250ml beaker containing 95ml distilled water.
Then stir the solution using a glass rod.
To check the transparency of sand solution
Take some of the sand suspension in a test tube. Paste a small strip of cellophane paper
on one side of the test tube and view it from the other side. The cellophane paper is not
visible from the other side of the test tube. This indicates that a suspension is opaque.
To do the filtration of sand solution Place a funnel over a test tube using a clamp
stand. Then place a filter paper in the funnel. Now pour the sand suspension taken in another
test tube through the funnel. A clear filtrate is obtained.
Sand particles are seen on the filter paper. This indicates that suspended components of
a suspension can be separated by filtration.
To check the stability of sand solution
Take some sand suspension in a test tube and leave it in a test tube rack for 20 minutes.
You will note a gradual settlement of soil particles at the bottom of the test tube.
This indicates that a suspension is unstable and show settlement of heavier particles.
Colloids
For the preparation of a colloidal of starch in water:
Take 1g of starch powder in a 250ml beaker. From another beaker containing 100ml distilled
water, take 3ml of water into a measuring jar and pour this into the beaker containing
starch. Mix the solution well using a glass rod.
Heat the beaker containing the remaining 97ml of distilled over a Bunsen burner.
Pour the boiling water into the beaker containing starch. Stir it well using a glass rod and
then cool it. To check the transparency of starch solution
Take some of the colloidal of starch in a test tube. Paste a small strip of cellophane
paper on one side of the test tube and view it from the other side. The cellophane paper
can be seen vaguely from the other side of the test tube. This indicates that a colloid
is translucent.
To do the filtration of starch solution
Place a funnel over a test tube using a clamp stand. Then place a filter paper in the funnel.
Now pour the colloidal of starch taken in another test tube through the funnel. A translucent
filtrate is obtained. No residue is left on the filter paper. This
indicates that components causing colloid cannot be separated by filtration.
To check the stability of starch solution
Take some colloidal solution of starch in a test tube and leave it in a test tube rack
for 20 minutes. No change is observed. This indicates that colloids are stable. Their
solute particles do not settle down even after lapse of time.
For the preparation of a colloidal of egg albumin in water:
Take 1g of egg albumin in a 250ml beaker. From another beaker containing 100ml distilled
water, take 5ml of water into a measuring jar and pour this into the beaker containing
egg albumin. Mix the solution well using a glass rod.
Take the beaker containing the remaining 95ml of distilled water and pour it slowly into
the beaker containing Egg albumin. Stir it well using a glass rod. A clear solution is
obtained. Add a few drops of dil. HCl into this clear
solution and stir it well. The clear solution of albumin and water will become turbid.
To check the transparency of egg albumin solution .
Take some colloidal of egg albumin in a test tube. Paste a small strip of cellophane paper
on one side of the test tube and view it from the other side. The cellophane paper can be
seen vaguely from the other side of the test tube. This indicates that a colloid is translucent.
To do the Filtration of egg albumin solution
Place a funnel over a test tube using a clamp stand. Then place a filter paper in the funnel.
Now pour the colloidal of egg albumin taken in another test tube through the funnel. A
translucent filtrate is obtained. No residue is left on the filter paper. This
indicates that components causing colloid cannot be separated by filtration.
To check the stability of egg albumin solution
Take some colloidal solution of egg albumin in a test tube and leave it in a test tube
rack for 20 minutes. No change is observed. This indicates that colloids are stable. Their
solute particles do not settle down even after lapse of time.
Không có nhận xét nào:
Đăng nhận xét