Preparation of Standard Zinc Sulphate Solution:
Weight out about 7.18g of Zinc Sulphate heptahydrate, ZnSO4.7H2O into 250ml of volumetric flask. Make up the volume with distilled water. The solution will be about 0.1M
Preparation of EDTA Solution:
Weigh out about 9.3g of the disodium salt of EDTA and dissolve in a 250ml volumetric flask. The solution will be about 0.1M
Pipette out 25ml of the Zinc Sulphate solution into a 250ml conical flask. Dilute to 100ml with distilled water and add 2ml of NH3/NH4Cl buffer solution (pH~10) and 30-50mg of Eriochrome Black T indicator. Titrate with the EDTA solution. At the end point colour changes from wine red to blue.