Chem 11: Naming Hydrates 2.4.3
See p. 101 in BC Chem 11
Hydrates
A hydrate is a salt that has water molecules stuck between the salt atoms. The atoms of
salts form a framework, or lattice, and the water molecules are incorporated in between
the atoms. That means that it is fairly easy to get the water “out” by heating the hydrate.
The water is in the formula, but it is NOT in the chemical formula… it is “added” by
placing a dot between the formula and the number of water molecules.
For example:
CoCl2•6H2O
Is read as “ cobalt chloride hexahydrate.
Prefixes for Hydrates
MONO =1
DI = 2
TRI = 3
TETRA = 4
PENT or PENTA = 5
See p. 101-102 in BC Chem11
HEXA = 6
HEPTA = 7
OCTA = 8
NONA = 9
DECA = 10
1.
Naming Hydrates
Formulae of hydrate
Name
FeCl3 •4H2O
SnCl4 •5H2O
Ca(ClO4)2 •7H2O
Cu(ClO3)2 •3H2O
MgBr2 •4H2O
CuSO4 •5H2O
Na2Cr2O7•2H2O
MgSO4 •7H2O
NaCH3COO •3H2O
Ni3(PO4)2 •8H2O
2.
Writing Formulae for hydrates
Name of Hydrate
cobalt chloride hexahydrate
cuprous sulfite pentahydrate
lead (II) phosphate tetrahydrate
nickel (III) hypochlorite octahydrate
lithium acetate trihydrate
sodium bicarbonate decahydrate
plumbic oxalate heptahydrate
Formula
Chem 11: Naming Hydrates 2.4.3
See p. 101 in BC Chem 11
See p. 101-102 in BC Chem11