What happens when you add a few drops of iodine solution to a small amount of starch?

Question

What happens when you add a few drops of iodine solution to a small amount of starch solution in a small test tube...

Answer 1

It's the test for starch you are asking about.Iodine produces a blue/black colour with starch.

Answer 2

Starch agar is a simple nutritive medium with starch added. Since no color change occurs in the medium when organisms hydrolyze starch, we add iodine to the plate after incubation. Iodine turns blue, purple, or black (depending on the concentration of iodine) in the presence of starch. A clearing around the bacterial growth indicates that the organism has hydrolyzed starch.

Iodine has been added to this starch agar plate. The zone of clearing surrounding Bacillus megaterium and Bacillus subtilis indicate that both were able to hydrolyze starch.

Add Iodine-KI reagent to a solution or directly on a potato or other materials such as bread, crackers, or flour. A blue-black color results if starch is present. If starch amylose is not present, then the color will stay orange or yellow. Starch amylopectin does not give the color, nor does cellulose, nor do disaccharides such as sucrose in sugar.

Answer 3

A drak blue-black will produce  .It shows that starch is present in it.

Answer 4

A dark blue/black colour develops as the iodine reacts with the starch - this is a diagnostic test for starch.