Hydrated Compounds

Hydrated Compounds...

Have water molecules as part of their chemical formula
Contribute to the crystalline structure of the compound

HYDRATED vs ANHYDRIDES

Hydrated end up being ANHYDRIDES, which are chemicals that used to be hydrated.

Ordered (how they're arranged in space)=crystalline

What is the value of "n" for the hydrate of Magnesium Chloride H2O?
Mass of crucible = 22.130 g
Mass of crucible + hydrate = 25.290 g
Mass of crucible + contents after heating = 23.491 g

25.290 g (Cruc + Hyd) - 22.130 g (Cruc) = 3.160 (Hydrate)

23.491 g (after heating) - 22.130 g (crucible) = 1.361 g (Anhydrous)

25.290 g (hydrate) - 1.361 (anhydrous)
= 1.799 g H2O driven off

1.799 g H2O x 1 mol H2O    = .09983 mol H2O
                       18.02 g H2O

1.361 g MgCl2  x  1 mol MgCl2  =  .01429 mol MgCl2
                            95.21 g MgCl2

.09983 mol H2O    = 7
      0.01429
n = 7


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