It is often possible to change a hydrate into an anhydrous compound by heating it to drive off the water (dehydration).

[answerhappygod]

It is often possible to change a hydrate into an anhydrous
compound by heating it to drive off the water (dehydration). A
33.88 gram sample of a hydrate of CoCl2 was heated thoroughly in a
porcelain crucible, until its weight remained constant. After
heating, 26.52 grams of the anhydrous compound remained. What is
the formula of the hydrate?
2. How
many ATOMS of sulfur,
are present in 2.91 moles
of sulfur
tetrafluoride, SF4?
3. How
many MOLES of fluorine are
present
in 1.57×1022 molecules
of sulfur tetrafluoride?