Unit 1 PPA 1: Preparation of Potassium Trioxalatoferrate
Aim: The aim of the investigation was to prepare Potassium Trioxalatoferrate (III) from Ammonium Sulphate and then calculate the percentage yield.
Introduction
a) Ligand
The oxalate ion can act as a ligand as it binds to a central metal ion to form a complex ion by the donation of one or more electron pairs into unfilled metal orbitals.
In this case three negatively charged oxalate ions surround one positively charged Fe3+. The three oxalate ions attach themselves to the Fe3+ at six points creating an octahedral shape.
This results in the metal complex having a net total charge of -3.
b)
Potassium Trioxalatoferrate
07/03/10
c) Relevant Equations
Step 1: (NH4)2Fe(SO4)2.6H2O + H2C2O4 → FeC2O4 + H2SO4 + (NH4)HSO4 +6H20
Step 2: 6FeC2O4 + 3H2O2 + 6K2C2O4 → 4K3[Fe(C2O4)3] + 2Fe(OH)3
Step 3: 2Fe(OH)3 + 3H2C2O4 +3K2C2O4 → 2K3(Fe(C2O4)3) + 6H2O
Percentage Yield Calculation