This project contains topic "Effect of sodium carbonate on foaming capacity of Soap" with several observations to help class XII students for their projects.

1. Certificate
This is to certify that “ ______________” of
Class XII ‘__’ has satisfactorily
completed the project on “FOAMING
CAPACITY OF SOAP” under the guidance
of ________________________ during the
session 20__-20__.
Student's Sign Teacher's Sign

2. Acknowledgement
I'd like to express my greatest gratitude to
the people who have helped & supported me
throughout my project. I’ m grateful to
_________ for her continuous support for
the project, from initial advice &
encouragement to this day.
Special thanks of mine goes to my colleague
who helped me in completing the project by
giving interesting ideas, thoughts & made this
project easy and accurate.
I wish to thanks my parents for their
undivided support & interest who inspired me
& encouraged me to go my own way, without
which I would be unable to complete my
project. At last but not the least I want to
thanks my friends who appreciated me for my
work & motivated me and finally to God who
made all the things possible...

3. CHEMISTRY INVESTIGATORY PROJECT
FOAMING CAPACITY OF
SOAP
Under The Guidance Of Submitted By

4. CONTENTS
Acknowledgement...............................i
Certificate.............................................ii
Aim of the project................................iii
Introduction.........................................iv
Theory...................................................v
Procedure.............................................vi
Observations.......................................vii
Calculations........................................viii
Conclusions..........................................ix
Bibliography........................................x

5. Introduction
Soaps are sodium or potassium salts of higher fatty acids
like stearic, palmitic and oleic acids can be either
saturated or unsaturated. They contain a long
hydrocarbon chain of about 10-20 carbon with one
carboxylic acid group as the functional group. A soap
molecule a tadpole shaped structure, whose ends have
different polarities. At one end is the long hydrocarbon
chain that is non-polar and hydrophobic, i.e., insoluble in
water but oil soluble. At the other end is the short polar
carboxylate ion which is hydrophilic i.e., water soluble but
insoluble in oil and grease.
When soap is shaken with water it becomes a soap
solution that is colloidal in nature. Agitating it tends to
concentrate the solution on the surface and causes
foaming. This helps the soap molecules make a
unimolecular film on the surface of water and to penetrate
the fabric. The long non-polar end of a soap molecule that
are hydrophobic, gravitate towards and surround the dirt
(fat or oil with dust absorbed in it). The short polar end

6. containing the carboxylate ion, face the water away from
the dirt. A number of soap molecules surround or encircle
dirt and grease in a clustered structure called 'micelles',
which encircles such particles and emulsify them.
Cleansing action of soaps decreases in hard water. Hard
water contains Calcium and magnesium ions which react
with sodium carbonate to produce insoluble carbonates of
higher fatty acids.
2C17H35COONa + Ca2+
→ (C17H35COO) 2 Ca↓ + 2Na+
(Water soluble) (ppt.)
2C17H35COONa + Mg2+
→ (C17H35COO)2 Mg ↓ + 2Na+
This hardness can be removed by addition of
Sodium Carbonate.
Ca2+
+ Na2CO3 → CaCO3 ↓ + 2Na+
Mg2+
+ Na2CO3 → MgCO3 ↓ + 2Na+

7. Aim
Study the effect of the addition of
Sodium Carbonate
(Washing Soda)
on the foaming capacity of
different soap solutions.

8. Apparatus:
3 test tubes, test tube stand, Bunsen burner and stop watch.
Materials Required:
0.5 g sample of soap, water (distilled & tap both) and M/10
Na2CO3 solution.

9. Theory:
When sodium or potassium soaps are put into water
containing calcium and magnesium ions (Hard water),
results in formation of scum which applies grey
appearance on the cloth. To achieve the same washing or
cleaning action, more soap must be added.
2C17H35COONa + Ca2+
→ (C17H35COO) 2 Ca↓ + 2Na+
(Water soluble) (ppt.)
Hard water is water that has high mineral content (mainly
calcium and magnesium ions) (in contrast with soft water).
Hard water minerals primarily consist of calcium (Ca2+
),
and magnesium (Mg2+
) metal cations, and sometimes
other dissolved compounds such as bicarbonates and
sulphates. Calcium usually enters the water as either
calcium carbonate (CaCO3), in the form of limestone and
chalk, or calcium sulphate (CaSO4), in the form of other
mineral deposits. When Na2CO3 is added to tap water the
calcium (Ca2+
), and magnesium (Mg2+
) ions precipitate as
their carbonates .i.e. foaming capacity of soap increases.
Ca2+
+ Na2CO3 → CaCO3 ↓ + 2Na+
Mg2+
+ Na2CO3 → MgCO3 ↓ + 2Na+

10. Procedure:
I. Dissolve 0.5g of soap and dissolve it in 50 ml of
distilled water.
II. Take three test tubes and add distilled water in
first, tap water in second and third test tube.
III. Add 5 ml of M/10 sodium carbonate to third test
tube.
IV. To above test tubes add soap solutions separately.
V. Now shake first test tubes for formation of foam.
VI. Now start the stop watch to calculate time taken
for disappearance of foam.
VII. Similarly, perform the experiment with other soap
solutions.
VIII. Record the observations in a tabular form.

11. Observations:
Amount of each soap sample taken = 0. 5 gm.
Amount of distilled water taken = 50 ml.
Volume of each soap solution take = 1 ml.
Volume of distilled water added = 10 ml.
Conclusions:
Foaming capacity of soap is maximum in distilled
water.
The foaming capacity of soap increases on the
addition of Sodium Carbonate.
S.no. Water Used Time Taken
1. Distilled Water 15'12''
2. Tap Water 8'45''
3. Tap Water + 5ml
M/10 Na2CO3
13'24''

12. Bibliography