Question

Iodine test is used to confirm the presence of
A. Fats
B. Proteins.
C. Vitamins.
D. Carbohydrates.

Answer 1

Starch is frequently utilized in chemistry as a marker for redox titrations where triiodide is shown. Starch shapes an awfully dull blue-black complex with triiodide.

Complete answer:
The iodine arrangement is utilized to distinguish the nearness of the carbohydrates within the arrangement. For the most part, the test is performed to identify the presence of starch which may be a carbohydrate. When there's the nearness of starch within the test arrangement, the colour of the arrangement turns bluish-black after the expansion of the iodine arrangement. Utilizing iodine to test for the nearness of starch may be a common exploration. An arrangement of iodine and potassium iodide in water encompasses a light orange-brown colour. In the event that it is included in a test that contains starch, such as the bread imagined over, the colour changes to a profound blue. The iodine–starch test may be a chemical response that's utilized to test for the nearness of starch or for iodine. The combination of starch and iodine is escalation blue-black.

Hence, the correct answer is option (D).

Note: The triiodide anion right away produces a strong blue-black colour upon contact with starch. The escalation of the colour diminishes with expanding temperature and with the nearness of water-miscible natural solvents such as ethanol. The test cannot be performed at exceptionally moo pH due to the hydrolysis of the starch beneath these conditions.