Question

Boojho took some grains of boiled rice infirst test tube and Paheli took boiled and chewed rice in other test tube . Both of them poured 1 – 2 drops of iodine solution into the test tube and observed the colour change.​

Answer 1

the saliva breaks down starch to sugar thus no color change occur but the boiled rice is rich in starch so it will change to blue black color

Answer 2

Explanation:

In test-tube A, the boiled rice contains starch. When we add 1-2 drops of iodine, the combination turns in the shade of blue-black. This indicates the presence of starch in the test tube A.  

In test-tube B, the starch of rice converts into sugar on digestion. Thus, the colour of iodine will not change.