How would you test a colorless crystalline compound to determine if it was hydrate?

To test if a colorless crystalline compound is a hydrate, gently heat a small sample of the compound in a dry test tube. If it loses weight and produces water vapor, it likely contains water of crystallization. You can also perform a qualitative test by adding a few drops of a cobalt(II) chloride solution; if the compound turns blue upon heating, it indicates the presence of water. Finally, measuring the weight before and after heating can confirm the loss of water associated with the hydrate.