Expert: George Maxwell - 7/20/2007

Question
Sir,

Can we convert water into some solid crystal which cannot be converted back to water. Please explian in brief if that is possible.

Thank you,

Hafeez Basha R

Answer
Thank you very much for your question.

In short, I don't think it's ever really possible to 'convert' water in to a form which cannot be turned back to liquid water.

The nearest technology I can think of involves absorbing liquid water in to a solid, using the matrix structure of a crystal system.

For example, Sodium Polyacrylate can absorb up to 800 times its own weight in water to form a stable gel. However, heating this gel sufficiently will release the trapped water as a vapour.

The only other theoretical approach involves modifying the structure of normal ice to make it less prone to melting.

For example, a 30% mixture of wood pulp in water, when frozrn, forms a substance known as Pykrete, which maintains its solidity for long periods at room temperature, and is mechanically much stronger than regular ice. Again, though, sufficient heat will turn it back in to liquid water.

The reason that your challenge is a difficult one is that it goes against the laws of thermodynamics: liquid water is more disordered ("has a greater enropy") than solid water, and -as far as we know- the entropy of a system always tends to increase. Thus, in any system where you have converted water to a solid, it will have an overall tendancy to revert to a liquid state.

I hope this is of value to you, but please do not hesitate to contact me again if you have any further questions on this topic.

Many Thanks.