Question

5. Iodine reacts with starch to form a blue-colored complex. Explain the results of the iodine test with the hydrolyzed starch solution. 6. Sucrose differs from honey in that honey is a mixture of glucose and fructose. Sucrose is a dis- accharide made up of them. Explain why honey is a quicker source of energy than sucrose.

Answer 1

So present in the solution is tri-jodide Solution : 6 Iodine solution in a solution of elemental iodine in another solution of iodide, usually KI- So present in the solution is to Ton 3 iodine in a struight line with a single negative charge Starch can take several shape but one of the shapes like a is like a helix. When the iodine is added to the starch, the tri-eiodide ion is right shape and size to fit into the helix shape of the starch, so it does so It forms a starch-tri-jodide complex. This complex has the ability to absorb all of the visible light and give blue color. If your t are testing a starch, even in small amounts using iodine to give blue color kelhen starch is hydrolyzed into smaller carbohydrates units, the blue color is not produced. Therefore, this test can also indicate completion of hydrolysis when a color change does not occur.