question_answer 42)

    A few drops of iodine solution were added to rice water. The solution turned blue-black in colour. This indicates that rice water contains (a) complex proteins     (b) simple proteins          (c) fats                                  (d) starch

Answer:

                  (d) The blue-black colour of rice water confirms the presence of starch. No colour change will be seen in case of proteins or fats in iodine solution colour, when iodine is added with them.