Procedure for preparation and standardization of 0.1N ammonium thyiocyanate

1. OBJECTIVE
To lay down the procedure for preparation and standardization of 0.1N ammonium Thiocyante

2. SCOPE
This procedure is applicable to Quality Control Department

3. RESPONSIBILITY
• Officer QC
• Manager QC

4. SAFETY INSTRUCTIONS
• Proper handling the apparatus.
• Proper handling the chemicals

5. PROCEDURE
5.1 PREPARATION
5.1.1 Take about 100ml of water in a cleaned and dried 1000ml volumetric flask
5.1.2 Add about 7.612gm of ammonium thiocyante to sufficient water with continuous stirring
5.1.3 Add more about 700ml of water, mix and allow to cool to room temperature
5.1.4 Make up the volume 1000ml with water. Mix solution thoroughly
5.2 STANDARDIZATION
5.2.1 Accurately measure about 30ml of 0.1N silver nitrate VS into a glass stoppered flask.
5.2.2 Dilute with 50ml of water, then add 2ml of nitric acid and 2ml of ferric ammonium sulfate TS
5.2.3 And titrate with the ammonium thiocyanate solution to the first appearance of a red brown color
5.2.4 And calculate the normality by the following formula:

N= —————————

6. RELATED DOCUMENTS

N/A

7. DISTRIBUTION INDEX
Original Copy will be retained by Quality Assurance Department.

8. ABBREVIATIONS
Q.C Quality Control Department
TS Test Solution
Vs. Against
Gm Gram
ml Millilitre

9. REVISION HISTORY