Question

While using iodine in a laboratory some drops of iodine fell on prayas sox and some fell on her teachers saree the drops of iodine on the saree turned blue black

Answer 1

Sarees are generally polished with starch and since iodine reacts with starch to form a complex which changes the color of the starch to blue black, the Saree's color changed to blue-black.

But the same is not the case with socks since they are not polished with starch. As there is no starch, there is no color change.