Question

solution turns blue after addiction of starch explain

Answer 1

When starch is mixed with iodine in water, an intensely colored starch/iodine complex is formed. Many of the details of the reaction are still unknown. But it seems that the iodine (in the form of I5- ions) gets stuck in the coils of beta amylose molecules (beta amylose is a soluble starch). The starch forces the iodine atoms into a linear arrangement in the central groove of the amylose coil. There is some transfer of charge between the starch and the iodine. That changes the way electrons are confined, and so, changes spacing of the energy levels. The iodine/starch complex has energy level spacings that are just so for absorbing visible light- giving the complex its intense blue color.
The complex is very useful for indicating redox titrations that involve iodine because the color change is very sharp. It can also be used as a general redox indicator: when there is excess oxidizing agent, the complex is blue; when there is excess reducing agent, the I5- breaks up into iodine and iodide and the color disappears

Answer 2

Answer:

Explanation:

If the iodine is mixed up with the starch solution in which the saliva is mixed the solution will change its colour to the blue-black colour but if the color does not change the color then the solution is wrong of the quantity of the starch is less than the actual quantity and then if the starch is not there then the color will not be the blue-black.