Study of rate of
evaporation of
different liquids
INDEX
I. OBJECTIVE
II. THEORY
III. MATERIALS RECQUIRED
IV. PROCEDURE
V. OBSERVATION
VI. CONCLUSION
VII. BIBLIOGRAPHY
This project would not have been possible
without the kind support and help of many
individuals. I would like to thank our
principal, Mr.M.Pradeesh Kumar for his
priceless motivation. I would also like to
thank our subject teacher; Mrs.Anita and
Mrs.Raghendu whose valuable guidance
helped me patch this project. I would like to
thank my parents for their heartfelt support
and encouragement. My thanks to my fellow
classmates in developing the project.
Rate of Evaporation of Different
Liquids
Objective of Project
In this project, we shall investigate
various factors such as nature of liquid,
surface of liquid and temperature and
find their correlation with the rate of
evaporation of different liquids.
THEORY
Factors influencing rate
ofEvaporation:1. Concentration of the substance
evaporating in the air.
If the air already has a high
concentration of the substance
evaporating, then the givensubstance will
evaporate more slowly.
2. Concentration of other substances in the
air.
If the air is already saturated with other
substances, it can have a lower capacity
forth substance evaporating.
3. Temperature of the substance.
If the substance is hotter, then
evaporation will be faster.
4. Flow rate of air.
This is in part related to the
concentration points above. If fresh air
moves over the substance all the time,
then the concentration of thesubstance
in the air is less likely to go up with time,
thus encouraging faster evaporation. In
addition, molecules in motion have more
energy than those at rest, and so the
stronger the flow of air, the greater the
evaporating power of the airmolecules.
5. Inter-molecular forces.
The stronger the forces keeping the
molecules together in the liquid or solid
state the more energy that must be input
in order to evaporate them.
6. Surface area and temperature.
The rate of evaporation of liquids varies
directly with temperature. With the
increase in the temperature, fraction of
molecules having sufficient kinetic
energy to escape out from the surface
alsoincreases. Thus with the increase in
temperature rate of evaporation also
increases. Molecules that escape the
surface of the liquids constitute the
evaporation.Therefore larger surface area
contributes accelerating evaporation.
7. Nature of Liquids
The magnitude of inter-molecular forces
of attraction in liquid determines the
speed of evaporation. Weaker the intermolecular forces of attraction larger are
the extent of evaporation.
8. Density
The higher the density, the slower a
liquid evaporates.
9. Pressure
In an area of less pressure, evaporation
happens faster because there is less
exertion on the surface keeping the
molecules from launching themselves.
MATERIALS REQUIRED
APPARATUS:
 Three petridishes of diameter 10 cm
with covers.
 10 ml pipette.
 Stop watch.
CHEMICALS:
 Acetone
 Benzene
 Chloroform
Fig 0.1: Petridish used for experiment
Experiment no. 1
Aim:
To compare the rates of evaporation of
acetone, benzene and chloroform.
Requirement:
Three same size Petri dishes of diameter
10 cm, 10 ml. pipettes, stop watch,
acetone benzene and chloroform.
Procedure:
 Clean and dry all Petri dishes and
identify them as A, B and C.
 Pipette out of 10 ml. acetone in Petri
dish "A" with stopper similarly pipette
out of 10 ml. of benzene and
chloroform in each of Petri "B" and
"C".
 Remove the cover plates from all Petri
dishes and start the stop watch.
 Let the Petri dishes remain exposed
for 10 minute. Now cover each of the
petridish and note the volume of
remaining material in them.
Observation:
Time: 10 min = 600 Sec.
Liquid
Vol.
Petri
Volume
Taken
Evap.
dishes
remaining
Rate (V/T) ml./s
(V1)
V=V1–
Marked
(V2) ml.
ml.
V2
A
B
C
10
10
10
2
3
4
8
7
6
8/600=0.0133
7/600=0.0116
6/600=0.010
Results:
Rate of evaporation of Acetone is 0.0133
ml/s.
Rate of evaporation of Benzene is 0.0166
ml/s.
Rate of evaporation of Chloroform is
0.010 ml/s.
Conclusion:
The intermolecular forces of acetone,
benzene and chloroform are in order.
Chloroform > Benzene > Acetone.
Fig1.1 Intermolecular forces
Experiment no. 2
Aim:
To study the effect of surface area on
the rate of evaporation of diethyl ether.
Requirement:
Three petri dishes of diameter 2.5 cm,
5cm, 7.5 cm with cover, 10 ml of pipette
and stop watch.
Procedure:
 Clean and dry all petridishes and mark
them as A, B and C.
 Pipette out 10 ml of diethyl ether in
each of the petridish A, B and C and
cover them immediately.
 Uncover all the 3 petridish and start
the stopwatch.
 Note the remaining volume after 10
minutes.
Observation:
Time: 10 minutes = 600 seconds.
Petri
Diameter of Volume Taken Remaining Evaporated
dishes
P.T.Ds.
(ml.)
Vol. (ml.) volume
Marked
A
B
C
2.5
5.0
7.5
10
10
10
4
2
0
6
8
10
Result:
The order of evaporation of acetone in
three petridish are as 7.5 > 5.0 > 2.5.
Conclusion:
Larger the surface area, greater the
evaporation.
Fig 2.1 Different petridishes with different surface areas.
Experiment 3
Aim:
To study the effect of temperature on
rate of evaporation of acetone.
Requirement:
Two petridish of 5 cm diameter, stop
watch, 10 ml pipette, thermometer,
thermostat.
Procedure:
 Wash, clean, dry the petridish and
mark them as A,B
 Pipette out 10 ml of acetone in each
of the petridish and cover them.
 Put one at room temperature and heat
the other.
 Note the reading.
Observation:
Time taken 10 minutes = 600 seconds.
Petri
Evaporated
Time Temperature Volume Taken
dishes
volume
(Sec.)
(0C)
(ml.)
Marked
(ml.)
A
B
10
20
30
40
10
10
10
10
Result:
Evaporation during heating is greater
than evaporation at room temperature.
Conclusion:
Evaporation increases with increase in
temperature.
Fig 3.1: Heating a petridish.
CONCLUSION
Rate of evaporation of the given three
liquids is in the order:
Chloroform=0.0133 ml./s
Benzene=0.0116ml./s
Acetone=0.010ml./s
Chloroform > Benzene > Acetone
 The intermolecular forces of acetone,
benzene and chloroform are in order.
 Chloroform > Benzene > Acetone.
 Larger the surface area, greater the
evaporation.
 Evaporation increases with increase in
temperature.
BIBLIOGRAPHY
 WWW.WIKIPEDIA.ORG
 WWW.CHEMWORLD.COM
 WWW.QUORA.COM
 WWW.ICBSE.COM