2.  substances that include water into their formula  water is not actually part of the chemical substance and this is reflected in the way the formula is written

3.  For every one CuSO 4, there are five water molecules  The dot IS NOT a multiplication sign. Remember, this is chemistry, not math.

4.  No, the substance is not wet, it appears dry.  There are some hydrates that have a wet appearance, but most appear perfectly dry to the eye and to the touch.

5.  penta meaning five and hydrate meaning water  CuSO 4. 5 H 2 O

7.  Suppose you heard "trihydrate." What would you write?

8. . 3 H 2 O

9.  Suppose you heard "octahydrate." What would you write?

10. . 8 H 2 O

11.  Name this substance: MgSO 4. 9 H 2 O

12.  Magnesium sulfate nonahydrate

13.  Write the formula for: barium chloride dihydrate

14.  BaCl 2. 2 H 2 O

15.  Keep water’s mass separate in calculation  CuSO 4. 5 H 2 O  Cu = 63.5 g  S = 32.1 g  O = 16.0 x 4 = 64.0 g  H 2 O = 18.0 g x 5 = 90.0g › Add them all together to get the molar mass  Total = 249.6 g (MOLAR MASS)

16.  Calculating the accepted value:  How much water did we have? › 90.0 grams H 2 O  What was the total molar mass? › 249.6 grams  90.0 g x 100 = 36.1% H 2 O 249.6 g

17.  You begin an experiment with 15.0 grams of hydrate.  You place the hydrate in an evaporating dish and place the Bunsen burner below.  You weigh your resulting product, 13.2 grams of anhydrous salt (a compound with all the water removed).  Determine the experimental percent composition of water within the compound

18.  15.0 grams – 13.2 grams = 1.8 grams of water that was evaporated (removed)  1.8 g x 100 = 12.0% H 2 O 15.0 g