Answer:
The chemical formula is FeCL3* 6H2O
The name of this hydrate is Iron(III) Chloride Hexahydrate or Ferric Chloride Hexahydrate
Explanation:
Step 1: Data given
Mass of FeCl3 * xH2O = 5 grams
mass of H2O = 2 grams
Molar mass of FeCl3 = 162.2 g/mol
Molar mass of H2O = 18.02 g/mol
Step 2: Calculate mass of FeCl3
After heating, the remaining mass, is the mass of FeCl3, because H2O (2 grams) is driven off.
Mass FeCl3 = 5-2 = 3grams
Step 3: Calculate number of moles
Number of moles = mass / molar mass
Moles of FeCl3 = 3.00 grams / 162.2 g/mol = 0.0185 moles
Moles of H2O = 2.00 grams / 18.02 g/mol = 0.111 moles
Step 4: Divide the number of moles by the smallest number of moles
The smallest number is 0.0185; so we will divide both by 0.0185
FeCl3 = 0.0185 /0.0185 = 1
H2O = 0.111 / 0.0185 ≈ 6
This means for 1 mole of FeCl3 we have 6 moles of H2O
The chemical formula is FeCL3* 6H2O
The name of this hydrate is Iron(III) Chloride Hexahydrate or Ferric Chloride Hexahydrate
