What is anhydrous?

Answer 1

A hydrated crystal in one that has water molecules trapped inside the crystal structure of some other compound, typically an ionic compound. The water is chemically combined with a substance in such a way that it can be removed, as by heating, without substantially changing the chemical composition of the substance. As a good example, copper sulfate is a commonly hydrated crystal. To show that it is hydrated, you would write CuSO4 . 5H2O. By putting a dot in between the two, it indicates that they are waters of hydration, not really part of the compound (you can remove them by heating the crystals). You can see in this case, there are 5 water molecules for each CuSO4.

Answer 2

An anhydrous salt is a salt that has been heated up until the water in it evaporates and it usually disintegrates into a powder, but is now anhydrous (without water). Anhydrous means when the salt is crystallizing, no water is captured within the crystal matrix.

Answer 3

A anhydrous crystal is one that has had all of the water molecules removed from it, usually by heating the hydrated crystal to a constant mass.

Answer 4

containing no water, esp no water of crystallization

Answer 5

A liquid that lacks the presence of water. For example, liquid gold; which liquefies at such a temperature that any water present would vaporize.