On Wed, 29 Sep 1999, Allen Dick wrote:
>
> To me, a dihydrate should be an acid molecule with two molecules of water.  But,
> I should also have imagined that the dihydrate would be liquid.  Maybe not.
>
> To those who use have used oxalic acid dihydrate:  what exactly is the dihydrate
> form?
Quoting from the Penguin Dictionary of Chemistry:

"Oxalic acid, C2H2O4, crystallizes from water in large colourless prisms
containing two water molecules."

Lots of molecules crystallize in forms that contain one or more molecules
of water as part of the crystal structure. Honey is one of them.

Best regards,

Donald Aitken
Edmonton Alberta Canada