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 color did not change on the socks. What can be the possible reason?

Starch turns blue black with iodine solution. The saree of Paheli’s teacher might have been starched so, it turns blue black. Paheli’s socks did not have starch so it remained as such.

The effect of adding iodine is shown below:



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