Get the latest updates from us for free
Android App

Preparation and Standardization of 0.1 M Zinc Sulphate


Preparation and standardisation of the 0.1 M Zinc Sulphate using Dithizone as indicator used for the analysis of pharmaceutical materials.

Zinc Sulphate Solution Preparation:


•  Take about 100 ml of purified water in a cleaned and dried 1000 ml volumetric flask.
•  Add about 28.8 gm of zinc sulfate with continues stirring.
•  Add more about 700 ml of purified water, mix and allow to cool to room temperature.
•  Make up the volume 1000 ml with purified water. Mix solution thoroughly.
•  Keep the solution for at least an hour and than carryout the standardization.

Zinc Sulphate Solution Standardization:

Method I

•  Take 10 ml of previously standardised 0.1 M EDTA solution into a clean & dried conical flask.
•  Add about 4 gm ammonium acetate.
•  Add 10 ml of acetic acid-ammonium acetate buffer. (7.71 gm of ammonium acetate in water + 5.7 ml acetic acid to produced 100 ml with purified water).
•  Add 50 ml alcohol shake well.
•  Add 2 ml Dithizone TS. As an indicator.
•  Titrate the above solution with 0.1 M zinc sulphate with constant stirring and until the solution gives clear, rose pink color.
•  Note down the burette reading.
•  Calculate molarity of solution by following formula:


                                                         Molarity of EDTA x 10
 Molarity of 0.1 M Zinc sulphate  =  ----------------------------------
                                                               Burette Reading


Method II

•  Take 20.0 ml solution into a 500 ml conical flask.
•  Add 5 ml of 2 M acetic acid and dilute to 200 ml with water. 
•  Add about 50 mg of xylenol orange and hexamethylenetetramine until the solution becomes violet-pink. 
•  Add 2 g of hexamethylenetetramine in excess. 
•  Titrate with 0.1 M disodium edetate until the violet-pink colour changes to yellow.
•  1 ml of 0.1 M disodium edetate is equivalent to 0.02875 g of ZnSO4.7H2O.

Also see: Determination of Shelf Life of Solutions in Laboratory

Ankur Choudhary is India's first professional pharmaceutical blogger, author and founder of Pharmaceutical Guidelines, a widely-read pharmaceutical blog since 2008. Sign-up for the free email updates for your daily dose of pharmaceutical tips.
Email: .moc.enilediugamrahp@ofni Need Help: Ask Question


Be the first to comment!

Post a Comment