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If you are looking at a iodide to iodine redox titration, the solution would turn yellow instead of blue/black. The blue/black color of the iodine-starch complex is very intense and so the end-point is sharper. Without the starch, the endpoint, when the first yellow from the formation of iodine I2, appears, is less sharp and is harder to see.
Yellowish brown
Phenolphthalein is an acid base indicator - it does not show the end-point in a thiosulfate type titration. Starch gives a very sharp end-point from a blue-black to colorless end-point when titrating iodine with thiosulfate. Phenolphthalein would just not detect this change.
The color would be a yellowish-orange.
A deep blue colour
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Iodine is famous for testing of the presence of starch. I would assume starch is present in the solution, therefore iodine would turn blue. Originally, the colour of iodine solution is brown.
Iodine solution is commonly used to test for starch. If starch is present in a substance (e.g. a leaf which undergone photosynthesis) then the iodien solution would turn blue black. If no starch is present then it remains as light brown.
A dye would be needed if iodine were not available. The ingredients can also be scientifically measured to tell whether or not hydrolysis had occurred.
To detect starch hydrolysis on a starch agar plate, you can add iodine solution. Iodine reacts with starch to form a blue-black color, and if starch is hydrolyzed by the organism, the clear zone around the bacterial growth will indicate the presence of amylase, an enzyme that breaks down starch.
Iodine solution is commonly used to test for starch. If starch is present in a substance (e.g. a leaf which undergone photosynthesis) then the iodien solution would turn blue black. If no starch is present then it remains as light brown.
A student adds iodine solution to egg white and waits for a color change. How long will the student wait?
Perhaps the iodine solution was old and gave a false negative.
If you are looking at a iodide to iodine redox titration, the solution would turn yellow instead of blue/black. The blue/black color of the iodine-starch complex is very intense and so the end-point is sharper. Without the starch, the endpoint, when the first yellow from the formation of iodine I2, appears, is less sharp and is harder to see.
A deep blue colour
Sugars - Benedict's solution Fats - Brown Paper Starch - Iodine Protein - Biuret Solution