Q: How do you spell dessicater?

A: Desiccator.

Q: What color should the desiccant be?

A: Blue. If it has turned pink, have it recharged.

Q: How long do I let my sample dry?

A: At least overnight.

Q: Should I have the cap on the vial?

A: No, it won't dry if water vapor can't diffuse out to be absorbed by the calcium sulfate ("Drierite") desiccant.

Q: Can I use the desiccator to remove other solvents, like dichloromethane?

A: No. It works by forming a hydrate of the inorganic salt (calcium sulfate in our lab), and is specific in its action to water.

Q: How can I be sure if my sample has finished drying?

A: You can "dry to constant weight." Weigh the sample, and verify the weight no longer decreases with time in the desiccator.

©2001,2002 Daniel A. Straus