GROUP 3Azis Dwi Septianto
Billy Dimas Anggoro
Maghfira Firstia Mulyawan
Mohammad Suhud Farabi
Prambudi Cahyo Laksono
Prasetia
Definition of Indicator
Yodometri Indicator
Kanji’s Indicator
Example of Yodometri Titration
Definition of
IndicatorIndicator is a chemical
substrate that added into a
titration which give a change of
color when the endpoint
reached.
Indicator usually used at
a reaction of titration that
the change is invisible or
only just to clear a
Yodometri
IndicatorTitration in yodometric actually
can do without the addition of
indicator from outside because the
color that produce by I2 that
titrated by Tio will be dissolved
when endpoint reached.Generally, first the change of the color is dark
brown, then become light brown, then turn intoyellow, light yellow, until in the end the color ofsolution will be disappear.
When it observed, the color is
clear enough because the
There are several types of
indicators may be used in redox
titration. Among them are the
specific indicators, are
substances that cause reactions
in a specific way with one of the
reactants in the titration to
produce colors such as dark
blue starch with iodine.
make starch as an important
energy source.
Amylum or starch is a
Kanji can be separated
into two primary
components such amylose
( ) which long and straight
chain, is abundant in potato
starch , and gives blue color
with Yod. And amylopectin
( ) which has a long chain
but branched, and form a
product that purple–red.
Amylose
Amylopectin
In daily language, word
“starch” always mixed with
“flour” and also “kanji”.
Starch is a primary compose of
flour. Flour can be may not
only contain pure starch, it can
be mixed or blended with
protein, vitamins, and other
materials contained in the
grains of rice.
C o l o r e d c o m p l e x
f o r m a t i o n m e c h a n i s m
i s n o t p r e c i s e l y
k n o w n . H o w e v e r , t h e
i o d i n e m o l e c u l e s
a r e h e l d o n t h e
s u r f a c e o f a m y l o s e , a
s t a r c h e l e m e n t .
E l e m e n t s o f o t h e r
s t a r c h a m y l o p e c t i n
f o r m a c o m p l e x t h a t
i s r e d d i s h (v i o l e t )
w i t h i o d i n e , w h i c h i s
it’sthat
amylopectinindicator.
easilyit
addition,
The main advantage of kanji is cheap.
But the disadvantages, such as:
1. Insoluble in cold water
2. Unstable suspense in water
3. With Iod give a complex that insoluble in
water, so kanji can’t be added in the
beginning of the titration.
Kanji can’t be added into a highly acidic
medium because it can occurs hydrolysis
of the kanji. And also the addition of the
etanol 50% or more because the color
won’t be appear.
The Example Of
Yodometri Titration
Y o d o me t r i i st i t r a t i o n w i t h r e d o xme t h o d . T h i st i t r a t i o n i s i n d i r e c tt i t r a t i o n , w h e r en e e d e d o t h e rs u b s t a n c e b e f o r et i t r a t e d w i t h T i os o l u t i o n .
A n d t h i s i s a ne x a mp l e o f s u b s t a n c et h a t i t p e r c e n t a g ec a n b e d e t e r mi n a t e d
T h i s p r o c e d u r e b a s e
o n r e a c t i o n b e t w e e n
c h l o r a t a n d i o d i d e
w i t h c o n c e n t r a t e d
c h l o r i d e a c i d :
i o d t h a t p r o d u c e d a r e
t i t r a t e d w i t h T i o
s o l u t i o n .
I n o t h e r m e t h o d e ,
t h i s c h l o r a t i s
r e d u c t e d w i t h b r o m i d e
O3H3ICl6HI6ClO 22
---
3
O3H3BrCl6H6BrClO 22
---
3
Determination The Content of
Cu (II) in CuSO4.5H2O by “De
Haens” WayIn acidic conditions, Cu (II) can be
reduced to CuI2 which then decompose intoCu2I2 and I2. Thereafter, the free I2 titratedwith Na2S2O3 (sodium thiosulfate) andstarch indicator when approaching theendpoint. Cu (II) reduced by KI. The endpoint of this designation is from blue tocolorless and milky white precipitateformed.
Reaction
422
4 SOK2white
2CuI 4KI 2CuSO
222
2 Iemilky whit
ICuCuI2
6423222 OSNa NaI2OS2NaI
Determination of
Normality of Na2S2O3
with BBP KIO3In acidic conditions, can be
oxidized by KIO3 KI to iodine (I2)
that have free brown. Free I2 then
titrated with Na2S2O3 until a
slight yellow color. The addition
of starch as an indicator of the
blue and make the solution
obtained colorless endpoint.
OH3I3KCl6HCl6KI5KIO 223
6423222 OSNa NaI2OS2NaI
Any Question So Far?