ChemistryName________________ Experiment # _____Section_____Date_____ Percent of Water in Copper II Name(s) of Lab Partner(s) Sulfate Pentahydrate

 To calculate the percent of water in a hydrate

1.Mass a dry watch glass 2.Add a small scoop of blue hydrate 3.Mass the watch glass and hydrate 4.Heat the hydrate on hot plate until all blue is gone 5.Allow watch glass to cool 6.Mass the watch glass and anhydrate 7.Carefully add a few drops of water to the watch glass and observe. 8.Clean up.

 Mass of watch glass______  Mass watch glass and hydrate______  Mass watch glass and anhydrate______

 Before heating- (3)  During heating- (3)  After adding water- (3)

 Percent of water in CuSO 4 · 5 H 2 O  1. Amount of hydrate = __________  2. Amount of anhydrate = _________  3. Amount of water = _________  4. Experimental percent of water - ___________

 5. Actual Percent of Water in CuSO 4 · 5 H 2 O **hint – set up the table with percent composition for water**  6. Percent error  Percent error = actual %– experimental % X 100 = ____ % actual %

 The mass percent of water in copper sulfate pentahydrate is _____________. The actual percent is ________. My percent error is __________. Two sources of error include __________.