Question

rice in test tube B did not turn blue black . why?​

Answer 1

Since test tube B has boiled rice which were chewed for 3-5 minutes, the saliva present in mouth has acted upon starch to break down into sugars. So it does not show any colour in presence of iodine solution.....

Answer 2

Answer:

Conclusion: Since test tube B has boiled rice which were chewed for 3-5 minutes

Explanation:

the saliva present in mouth has acted upon starch to break down into sugars. So it does not show any colour in presence of iodine solution.