Question

While using iodine in the laboratory, some drops of iodine fell on Paheli’s socks and some fell on her teacher’s saree. The drops of iodine on the saree turned blue black while their colour did not change on the socks. What can be the possible reason?

Answer 1

The saree of Paheli’s teacher might have been starched. As starch turns blue black with iodine solution, so the saree also turned blue-black. Paheli’s socks did not have starch thus did not show any colour change.