Why can’t you undo a heated hairstyle with cold?

Question

Example: if I straighten my hair, washing it in water will un straighten it, but being in super cold air won’t.

In: Chemistry

Answer 1

It’s like boiling an egg – once you boil it, even if put into a freezer it won’t turn back.

The same analogy is for hair, the heat makes the hair stay put, while water softens the hair and allows it to reshape.