Question

lodine turns_____ blue-black.​

Answer 1

Explanation:

Correct option is

C

Starch

The iodine test is used for the determination of the presence of starch in a sample. Molecular iodine is not soluble in water and hence potassium iodide is added to it. Together they form polyiodide complex which upon addition of starch turns intense blue-black colour. Starch is a polymer of amylose and amylopectin, of which amylose is responsible for the blue colour of the reaction. In the absence of starch solution remain as light brown colour which is the colour of iodine solution.

Answer 2

concentrate of iodine

Explanation:

present of starch that's why it turns to blue black colour