An anhydrous compound from a hydrate is generally highly soluble in water, and when dissolved in water it will be a similar color to that of the original hydrate, even if it changed color transforming from the hydrate to the anhydrous compound.

Are hydrated salts more soluble?

Hydrates are generally expected to be thermodynamically more stable, hence less soluble and slower to dissolve than anhydrate forms above the critical water activity for hydrate formation.

Are hydrated salts soluble in water?

Properties of Hydrates

Highly soluble in water. When dissolved in water, the anhydrous compound will have a color similar to that of the original hydrate even if it had changed color going from the hydrate to the anhydrous compound.