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Because starch forms a dark blue colored soluble product with free iodine, so that the appearance of color in the solution from this reaction effectively shows when all the substances in the solution that react more strongly with iodine than does starch have been consumed and the titration is finished.
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Why do you need freshly prepared starch solution for iodometric titration?
because,starch undergoes a photochemical reaction. So, with the passage of time it can under go to the photochemical reaction and starch wouldnot be starch but it might have changed in anyother product. so...we should use freshly prepared starch.
How do you overcome the disadvantages of starch indicator?
All the alpha amylase molecules should rupture . Boil water and then add to the boiling water required starch. Make sure that the starch is alpha and not beta amylase. Use freshly prepared starch solution for iodometric titrations. --unnikrishnan
What chemical indicator do you use for starch?
Starch is not the indicator. Iodine is the indicator of starch.
Why you use phenolphthalein in titration?
it acts as acid base indicator
How do you find concentration of an acid from a titration?
use phenol phtalein as an indicator
Why do you need freshly prepared starch solution for iodometric titration?
because,starch undergoes a photochemical reaction. So, with the passage of time it can under go to the photochemical reaction and starch wouldnot be starch but it might have changed in anyother product. so...we should use freshly prepared starch.
How do you overcome the disadvantages of starch indicator?
All the alpha amylase molecules should rupture . Boil water and then add to the boiling water required starch. Make sure that the starch is alpha and not beta amylase. Use freshly prepared starch solution for iodometric titrations. --unnikrishnan
What chemical indicator do you use for starch?
Starch is not the indicator. Iodine is the indicator of starch.
Why you use phenolphthalein in titration?
it acts as acid base indicator
How do you find concentration of an acid from a titration?
use phenol phtalein as an indicator
What color does the indicator turn when starch is present?
Iodine is used to indicate whether starch is present in a solution. If starch IS present, the indicator will turn dark blue/black. Iodine is used to indicate whether starch is present in a solution. If starch IS present, the indicator will turn dark blue/black. FOR WHAT PURPOSE WE USE STARCH-IODINE INDICATOR PAPER
Describe a method to visually detect the end point of a titration without the use of instruments?
The method used most often in chemistry labs is by use of a pH indicator in the sample being titrated. When you reach the titration point, the indicator will change colors, demonstrating the end point of the titration.
What is the best way to choose an indicator for use in titration?
Choose the indicator so that the end point and equivalance point are at the same volume.Type your answer here...
Which indicator is suitable for the titration of washing soda against HCL and why?
iv done the titration and the preferred indicator for such a solution is phenalphaline, use a few drops to make it go a bright luminous pink and titrate till clear, not 'cloudy'
What kind of indicators are used in precipitation titration?
An example of an indicator would be Phenol Red, or Universal Indicator. Depending on the pH range of the indicator and the pH range of the substrates you would use the appropriate indicator.
Can you use indicator other than phenolphthalein in the titration of NaOH?
Yes you can use methyl red, methyl orange, bromophenol blue and other indicators instead of phenolphthalein in the acid-base titration of NaOH.
Why starch indicator should be prepared freshly?
To prepare 1% starch indicator weigh 1g of starch powder.Measure 100ml of water and keep it for heating.by using some of 100ml water taken,make a paste of starch in watchglass and mix this paste with little and continuous strring of water which is kept for heating.when all the paste is added,allow for heating 5more minutes then starch indicator is ready for titration.Note:no lumps of starch should present in water
