Complexometric titration is a type of titration based on complex formation between the analyte and titrant. Complexometric titrations are useful for determining mixtures of metal ions in solution using an indicator with a marked color change to detect the endpoint. Complexometric titration can also be used to determine water hardness and is widely used in the medical industry due to its ability to work with microliter sample sizes. Common applications of complexometric titration include determining calcium content in cheese and phytic acid content. Acid-base and redox titrations are also important titration methods that have various applications in pharmaceuticals, biodiesel production, and determining vitamin C content in fruit juices among others.

1. Presented to: Dr. Sohaila
Presented by: Falak Naz
BS Chemistry (4)
APPLICATIONS OF TITRATION
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3. C o m p l e x o m e t r i c t i t r a t i o n i s a t y p e o f t i t r a t i o n b a s e d
o n c o m p l e x f o r m a t i o n b e t w e e n t h e a n a l y t e a n d t i t r a n t

4. • Complexometric titrations are particularly for
determination of mixture of different metal ions
in solution. An indicator with a marked color
change is usually used to detect the end point of
titration.
• Complexometric titration is an efficient method
for determining the level of hardness of water.
Caused by accumulation of mineral ions.
• Complexometric is widely used in the medical
industry because of the microliter size sample
involved.
• The method is efficient in research related to
the biological cell.
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5. Complexometric Determination
of Calcium in Cheese
• 2 t o 3 g o f c h e e s e a r e a c h e d ,
d i s s o l v e d i n d i l u t e a c i d , a n d a d d e d
c a l c i u m c h l o r i d e i s b a c k t i t r a t e d
w i t h E D T A u s i n g h y d r o x y n a p h t h o l
b l u e a s i n d i c a t o r .
• S a m p l e s r e m a i n f r e e o f t u r b i d i t y ,
a n d t h e t i t r a t i o n e n d p o i n t i s
r e c o g n i z e d e a s i l y .
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I m p o r t a n c e
I n t e r e s t i n t h e c a l c i u m c o n t e n t o f
c h e e s e , h a s h e i g h t e n e d r e c e n t l y , n o t
o n l y d u e t o t h e n u t r i t i o n a l s i g n i f i c a n c e
o f c a l c i u m b u t a l s o t o i t s r e l a t i o n s h i p
w i t h c h e e s e q u a l i t y

6. P R O C E D U R E
c h e e s e s a m p l e s ( 2
t o 3 g ) w e r e
w e i g h e d w i t h a n
a n a l y t i c a l b a l a n c e .
Samples were dried overnight
at 100°C and ashed at 600°C.
After cooling, the ash was
wetted with 1 to 2 ml distilled
water followed by .5 ml
concentrated sulfuric acid.
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7. P R O C E D U R E
A small amount of additional distilled water
was added, if necessary, to disperse the ash,
and the slurry was transferred quantitatively
to a 250-ml flask.
The crucible was rinsed repeatedly with
distilled water until volume in the flask was
about 50 ml. If the mixture remained turbid
the flask was shaken mechanically for several
minutes until a clear solution was obtained.
Sufficient EDTA, usually 15 to 20 ml
measured from a burette, was added to the
flask to titrate approximately all calcium in
the sample.
The solution was stirred
magnetically and 8 ml sodium
hydroxide followed by about
100 mg indicator were added,
yielding a blue solution if all
calcium was titrated or red-
purple solution if titration
was incomplete.
In the latter
case, additional
EDTA was added
until color was
blue. Calcium
content was
calculated by
calculations.
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8. D e t e r m i n a t i o n o f P h y t i c
A c i d b y C o m p l e x o m e t r i c
T i t r a t i o n o f E x c e s s o f
I r o n ( l l )
• Phytine, phytate and myo-inositol
hexaphosphate are synonymous terms
for an organic phosphate, defined by
most workers as the calcium -
magnesium salt of myo-
inositolhexaphosphoric acid or phytic
acid.
Importance
• Phytic acid (I) and its sodium salts
occur in plant seeds and organic
soils, in which they constitute an
important phosphorus reserve. They
abound in cereals with a centripetal
location so its determination is
important.
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9. R e a g e n t s
• P h y t i c a c i d s t o c k s o l u t i o n ,
0 . 0 1 0 M .
• H y d r o c h l o r i c a c i d , 0 . 4 M a n d
2 % .
• I r o n ( I I ) s o l u t i o n i n 0 . 6 %
• S u l p h o s a l i c y l i c a c i d s o l u t i o n ,
2 0 % . i n d i c a t o r
• G l y c i n e .
• E D T A d i s o d i u m s a l t s o l u t i o n ,
0 . 0 1 M .
• S o d i u m s a l i c y l a t e s o l u t i o n , 1 0 % .
• S o d i u m s u l p h a t e s o l u t i o n , 5 % .
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10. P R O C E D U R E
Place 20.0 ml of phytic acid solution, containing
20.0ml hydrochloric acid, 20.0 ml iron(II) solution
and 20.0 ml sulphosalicylic acid solution in a 100-ml
test-tube.
Shake gently and seal the tube with a rubber cork
through which passes a narrow 30-cm long glass
tube, to prevent evaporation.
Place the tube in a boiling water-bath for 15 min,
then allow it to cool or cool it with tap water.
If a white precipitate forms, make sure that it has all
settled; in many instances naturally occurring samples
contain no phytic acid.
Taking care not to shake the tube, pipette exactly
20.0 ml from the supernatant liquid into a flask and
add distilled water to about 200ml. Heat to about 70
“C and, titrate with 0.010 M EDTA solution until the
intense red - maroon colour changes to clear yellow.
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11. An acid-base titration is
an experimental procedure
used to determined the
unknown concentration of
an acid or base by
precisely neutralizing it
with an acid or base of
known concentration.
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12. A P P L I C AT I O N S
Acid-base
titrations, i.e. the
neutralization
reaction between
acids and bases,
are very
frequently
performed in the
pharmaceutical
industry
acid-base
titrations are
often used for
Purity analysis
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13. TITRATING WASTE VEGETABLE
OIL FOR BIODIESEL
PRODUCTION
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I m p o r t a n c e

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15. Acid-base titration of Ibuprofen in
tablets
• Ibuprofen is an organic compound (its chemical name
is (RS)-2-[4-(2-methylpropyl)phenyl]propionic acid)
widely used as nonsteroidal anti-inflammatory drug
applied in fever, arthritis, and as pain reliever.
• Numerous drugs contain this compound, the most
popular are Ibum, Ibufen, Ibumax, Ibuprofen,
Ibuprom, MIG, Nurofen, Modafen etc.
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16. P R O C E D U R E
•Pour ca. 50 mL of glycerol and ca. 50
mL of hot water to flask and heat it to
ca. 60⁰C (the liquid is hot but does not
burn).
•Add 2-3 drops of Phenolphthalein and
add slowly, drop by drop, your titrant
NaOH solution, stirring the content
vigorously until rose color appears. Add
titrant solution to the burette up to
initial mark or note the actual level of
it.
•Place the tablet in the flask, crush it
with your glass stirring rod. Add
additional 1-2 drops of indicator and
titrate the content until red color
appears.
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17. Determination of CaCO3 in toothpaste
Acid base Titration
• Toothpaste is a daily-life
product, which is used
essentially to clean our
teeth
• Its major ingredients are
silica, calcium carbonate
and fluorine
• One of the most essential
substances is Calcium
Carbonate
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18. B a c k T i t r a t i o n M e t h o d
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19. P R O C E D U R E
Taking sample Mixing HCl and toothpaste Adding indicatorHeating solution on hot pane
Titrate with 0.10 M NaOH until the color of the solution starting to change reaching the end point, check final pH and volume
of NaOH left in burette.
Checking initial pH
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20. R E D O X T I T R A T I O N
• A redox titration is based on a redox reaction between the analyte
and titrant.
• It may involve the use of a redox indicator and/or a
potentiometer.
• Oxidation-reduction titrations (redox) are used for checking the
purity of raw materials, fillers and preservatives.
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21. D e t e r m i n a t i o n o f A s c o r b i c
A c i d i n C o m m e r c i a l F r u i t
J u i c e s b y R e d o x T i t r a t i o n
• A number of commercial juices
of different brands are
available in the markets.
These juices are consumed
daily by all classes of
population all over the world.
• Ascorbic acid (AA) contents is
determined by a procedure
based on iodometric titration
where dark blue complex
forms in the presence of
starch at the end point
Ascorbic acid (AA)
also known as
vitamin C can be
obtained from fruits
or vegetables and
multi-vitamin
supplements
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22. I O D O M E T R I C
T I T R A T I O N
• In this method, iodine reacts
with ascorbic acid to produce
dehydroascorbic acid which is
a colorless product.
• Iodine also reacts with starch
to produce a dark blue
product
• In presence of both ascorbic
acid and starch, the iodine
preferably reacts with the
Vitamin C instead of the
starch. Therefore, when
iodine is added in the
presence of both substances,
the ascorbic acid reacts and
the products are colorless.
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23. P R O C E D U R E
• Preparing iodine solution
• Preparing starch indicator solution
• Preparing of drink sample
• Standardization of the iodine solution
with the Ascorbic Acid standard
solution
Titration
• Aliquot of the sample solution
prepared above transferred into a
conical flask, 2 ml of oxalic acid,
about 150 mL of distilled water and 1
mL of starch indicator solution.
• Samples were titrated with 0.005 molL
−1 iodine solution. The endpoint of
the titration was identified as the first
distinct trace of a dark blue-black
color due to the formation of starch-
iodine complex.
Iodine solution changes rapidly because
Iodine is a halogen gas that evaporates
quickly. Therefore, iodine solutions need
to be standardized all the time during the
experimental procedure. Ascorbic acid is
also susceptible to oxidation by
atmospheric oxygen over time. For this
reason, the sample was prepared
immediately before the titrations. In
addition to this, a small amount of oxalic
acid (2 mL) was added to standard
ascorbic acid solution in order to
minimize the probability of oxidation of
ascorbic acid.
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24. S o d i u m S u l f a t e o f C o s m e t i c s ( R e d o x
t i t r a t i o n B Y A u t o m a t i c P o t e n t i o m e t r i c
T i t r a t o r )
Importance
Sodium sulfate is a
substance being
harmless to human
contained in hot
spring and believed to
smooth the skin. It is
used as auxiliary agent
in powder shampoo. It
helps to absorb dirt
and stains with
surface active agent.
Lead sulfate
precipitates are
formed when Sodium
sulfate contained in
cosmetics is titrated
with lead ion solution
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25. Redox titration By Automatic
Potentiometric Titrator
With Potassium ferricyan
－ferrocyanide indicator
is added, as Sulfate ion
decreases, Fe(II)ion
changes to Fe(III)ion also
changing electrode
potential.
Depending on composition,
some cosmetics may not
show a sharp inflexion,
however, EP can be
determined by setting an
appropriate rate of change
(RC) for detection.
At the endpoint of sulfate ion
precipitation, only Fe (III) ion
remains with a sharp potential
inflexion, which is detected by the
platinum electrode, and thus
concentration of Sodium sulfate is
obtained from titration volume.
• Reagent
Titrant ： Lead nitrate
Solvent ： Ethanol
Indicator: Potassium
Ferricyan-ferrocyanide
Hydrochloric acid
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26. P R O C E D U R E
Preparation of sample in
a beaker, and adding of
HCl and Ethanol.
Adding Potassium ferricyan
－ferrocyanide test
solution.
Titration with Lead nitrate
up to the endpoint to
obtain Sodium sulfate.
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27. The Determination of
Hypochlorite in Bleach
An aqueous solution
of sodium
hypochlorite (NaOCl)
is a clear, slightly
yellow liquid, and is
commonly known as
bleach.
Aside from its
uses as a
bleaching agent,
sodium
hypochlorite
solutions are also
used as sterilizing
agents and in
water treatment.
Industrial uses
include agriculture,
food, paper
production, and
textiles. Sodium
hypochlorite is also
added to waste
water to reduce
odors.
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28. P R O C E D U R E
sodium hypochlorite,
hydrochloric acid,
iodide ion, and
starch are combined
to form a starch–
triiodide blue
complex that has a
concentration that is
proportional to the
amount of sodium
hypochlorite in the
solution.
the starch-
triiodide product
is titrated by
sodium
thiosulfate to
form a colorless
solution of
iodide,
dithionate, and
uncomplexed
starch
The hypochlorite acts as
a limiting reagent,
determining how much
triiodide is produced. We
can then titrate the
triiodide-starch complex
with the thiosulfate to
determine the
concentration of the
complex formed. This
can then be used to
calculate the initial
concentration of
hypochlorite.
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29. 7/8/2020
29REFERENCES
 Ismail, M., Ali, S., & Hussain, M. (2014). Quantitative determination of ascorbic acid in commercial fruit juices by redox
titration. Int. J. Pharm. Qual. Assur., 5, 22-25.
 Kindstedt, P. S., & Kosikowski, F. V. (1985). Improved complexometric determination of calcium in cheese. Journal of
Dairy Science, 68(4), 806-809.ChemBuddy. (2009). Back Titration [Online]. Available:
http://www.titrations.info/backtitration
 https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=&ved=2ahUKEwjqtIzlwKbqAhVHCxoKHYWTD68QFjA
AegQIAxAB&url=http%3A%2F%2Fwww.kyoto-kem.com%2Fen%2Fpdf%2Findustry%2FCosmeticsSoap%2FETIE-
00033.pdf&usg=AOvVaw3p3H6B3S4G-NJd5o9NgRII
 Colgate Salt Whitening Calcium+Fluoride. Colgate-Palmolive (Thailand) Ltd., 700/362 Bangna-Trad, km 57, Amphur
Muang, Chonburi 20000, Lot no. 10-1-5513295
 R. Garcia-Villanova, R. J. Garcia-Villanova and C. Ruiz de Lope Department of Chemical Analysis, Food Science and
Toxicology, Faculty of Pharmacy, University of Granada, Granada, Spain
 Shui-Ping Yang* and Ruei-Ying Tsai Department of Chemistry, National Changhua University of Education, Changhua
50058, Taiwan;
 https://www.kbcc.cuny.edu/academicDepartments/PHYSCI/PL/chm11/Documents/Bleac
h.pdf