Chemistry Project - Diffusion
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Transcript of Chemistry Project - Diffusion
Project Report
Project Report
Submitted
On
DiffusionDiffusionDiffusionDiffusion
Class – XII
Submitted To: Submitted By:
Mr. Sunil JangdaMr. Sunil JangdaMr. Sunil JangdaMr. Sunil Jangda Pankaj GillPankaj GillPankaj GillPankaj Gill
Dept. of ChemistryDept. of ChemistryDept. of ChemistryDept. of Chemistry Class Class Class Class –––– XII XII XII XII
Certificate
This is to certify that Pankaj GillPankaj GillPankaj GillPankaj Gill, student of Class XII , Mahendra Model Sr. Sec. SchoolMahendra Model Sr. Sec. SchoolMahendra Model Sr. Sec. SchoolMahendra Model Sr. Sec. School
has completed the project titled Variation of Conductance with Temperature in Electrolytes
during the academic year 2009-2010 towards partial fulfillment of credit for the Chemistry
practical evaluation of CBSE 2010, and submitted satisfactory report, as compiled in the
following pages, under my supervision.
Mr. Sunil JangraMr. Sunil JangraMr. Sunil JangraMr. Sunil Jangra
Department of Chemistry
Mahendra Model Sr. Sr. School
Acknowledgements
"There are times when silence speaks so much more loudly than words of praise to only as good as belittle a person, whose words do not express, but only put a veneer over true
feelings, which are of gratitude at this point of time."
I would like to express my sincere gratitude to my chemistry mentor Mr. Sunil JangraMr. Sunil JangraMr. Sunil JangraMr. Sunil Jangra
, for her vital support, guidance and encouragement - without which this project would not
have come forth. I would also like to express my gratitude to the staff of the Department of
Chemistry at Mahendra Model Sr. Sec. School for their support during the making of this
project.
(Pankaj Gill)(Pankaj Gill)(Pankaj Gill)(Pankaj Gill)
Aim
Study the Diffusion of Solids in Liquids
Introduction
When substances are brought in contact with each
other, they intermingle with each other. This
phenomenon is known as diffusion. Diffusion takes
place very rapidly in case of gases, to a lesser extent
in case of liquids, and not at all in the case of solids.
However, diffusion of solids in liquids does take
place, albeit at a very slow rate.
If a solid is kept in contact with excess of solvent in
which it is soluble, some portion of the solid gets
dissolved. This process is known as dissolution of a
solid in liquid, and it takes place due to the diffusion
of solid particles into liquid medium.
Molecules of solute are in constant random motion
due to the collision between molecules of solute and
that of the solvent. It is this physical interaction
between solute-solvent particles that leads to
diffusion.
Objective
To demonstrate that rate of diffusion depends upon
the following factors:
� Temperature: As temperature increases, the
kinetic energy of the particles increases. Thus,
the speed of particles also increases, which in
turn increases the rate of diffusion.
� Size of the particle: As the size of particle
increases, rate of diffusion decreases. This is
because the particles become less mobile in the
solvent.
� Mass of the particle: As the mass of the
particle increases, the rate of diffusion
decreases; as the particle becomes less mobile.
Experiment 1
To study diffusion when copper sulphate is brought
in contact with water (liquid).
Requirements
Copper sulphate (CuSO4) crystals, 100 mL beaker
Procedure
� Take about two grams of copper sulphate
crystals in 100 mL beaker.
� Add about 50 mL of water and allow it to stand
for few minutes.
� Note the development of blue colour in water.
� Allow to stand further till it is observed that all
copper sulphate disappears.
� Note the blue colour change in water.
Conclusion
When solids such as copper sulphate are brought in
contact with liquids such as water, intermingling of
substances, i.e., diffusion takes place.
Experiment 2
To study the effect of temperature on the rate of
diffusion of solids in liquids.
Requirements
Copper sulphate (CuSO4) crystals, three 100 mL
beakers, watch glass, wire gauge, burner, tripod
stand, thermometer, stop watch.
Procedure
� Take five gram of copper sulphate each in three
beakers.
� Pour 100 mL of distilled water slowly in one of
the beakers.
� Cover this beaker with a watch glass.
� Pour 100 mL of cold water in a second beaker
slowly.
� Place a third beaker containing 100 mL of water
on a tripod stand for heating.
� Observe the diffusion process which begins in all
the beakers.
� Record of copper sulphate the time taken for the
dissolution of copper sulphate in all the three
cases.
Observations
S.
No.
Temperature of Water Time Taken to
Diffuse
1 10 °C 18 minutes
2 25 °C 15 minutes
3 70 °C 7 minutes
Conclusion
The rate of diffusion of copper sulphate in water is in
the order as given below:
Beaker 3 > Beaker 2 > Beaker 1
Thus, the rate of diffusion varies directly with
temperature.
Experiment 3
To study the effect of size of particles on the rate of
diffusion of solids in liquids.
Requirements
Graduated 100 mL measuring cylinders, copper
sulphate (CuSO4) crystals of different sizes, stop
watch.
Procedure
� Add 50 mL of water to each of the three
cylinders.
� Take five gram each of big size, medium size,
small size crystals of copper sulphate, and add
them separately in three cylinders.
� Allow to them to stand for sometime.
� Note the time taken for blue colour to reach any
fixed mark in each of the cylinders and note the
observations.
Observations
S. No. Crystal size Time Taken to Diffuse
1 Big 19 minutes
2 Medium 13 minutes
3 Small 5 minutes
Conclusion
The rate of diffusion of copper sulphate in water is in
the order as given below:
Beaker 3 > Beaker 2 > Beaker 1
Thus, smaller particles undergo diffusion more
quickly than bigger particles.
Result
� When solids such as copper sulphate are
brought in contact with liquids such as water,
intermingling of substances, i.e., diffusion takes
place.
� The rate of diffusion varies directly with
temperature.
� Small particles undergo diffusion more quickly
than bigger particles.