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Hydrate Errors

APCHEM-LVCLUS

Consider a lab in which a hydrate is heated to determine the waters of hydration.

Which of the following errors would increase the calculated number of waters of hydration?

A

Touching the crucible and leaving fingerprints after heating (but before the final weighing).

B

Incomplete heating (not heating until a constant mass is obtained).

C

The hydrate sample was contaminated with another ionic substance that has a melting point much higher than 100 degrees Celsius.

D

While transferring the crucible containing the anhydrous material to the balance for massing, the crucible tongs touched the product, leaving some of the solid product on the tongs.