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Explain how you determined the water of hydration for your chemical compound?
What is the proper chemical formula and name of the hydrated compound that you tested? Make sure you include the ratio of water to nonwatery portions of the hydrated compound.
Explain how you determined the water of hydration for your chemical formula.
1 Answer
- Roger the MoleLv 73 weeks agoFavorite Answer
You have the last two lines in the table mixed up.
Mass of dehydrated sample = 44.35 g - 43.45 g = 0.90 g
Mass of water evolved = 44.97 g - 44.35 g = 0.62 g
(0.90 g MgSO4) / (120.3676 g MgSO4/mol) = 0.007477 mol MgSO4
(0.62 g H2O) / (18.01532 g H2O/mol) = 0.03442 mol H2O
(0.03442 mol H2O) / (0.007477 mol MgSO4) =
4.6 (the molar ratio of H2O to MgSO4)
Such numbers must be integers, so you report a ratio of 5, and the formula is:
MgSO4·5H2O
[Although this is a long way from 7, which is the accepted value. Apparently you didn't heat the crucible long enough.]
