Question

What happens to starch when iodine solution is added to it?

• A. The red iodine solution will stain the starch blue-black.
• B. The blue-black iodine solution will stain the starch red.
• C. The colorless iodine solution will stain the starch red.
• D. The colorless iodine solution will stain the starch blue-black.

Answer 1

The correct option is A

The red iodine solution will stain the starch blue-black.

Iodine solution is a bit reddish in color. It is prepared by adding elemental iodine $\left(I_2\right)$ to a Potassium Iodide solution $\left(KI\right)$ .

On adding the iodine solution to starch, the two react to produce a blue-black color.