Procedure for preparation and standardization 0.05 M Edetate Disodium

1. OBJECTIVE
To lay down the procedure for preparation and standardization of 0.05 M Edetate Disodium

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
• Always wear appropriate personal protective equipment when handling this chemical.

5. PROCEDURE
5.1 PREPARATION
5.1.1 Determine the molecular weight of edetate disodium. The molecular weight of edetate disodium is 372.24 g/mol.
5.1.2 Calculate the amount of edetate disodium needed to prepare the solution. To prepare a 0.05 M solution, you will need 0.05 moles of edetate disodium per liter of solution. Therefore, to prepare 1 liter of solution, you will need:
0.05 oles/L x 1 L = 0.05 moles
5.1.3 The mass of edetate disodium required can be calculated using the following formula:
Mass (g) = moles x molecular weight (g/mol)
Mass (g) = 0.05 moles x 372.24 g/mol
Mass (g) = 18.61 g
5.1.4 Weigh out 18.61gm of edetate disodium using a balance.
5.1.5 After measuring the required amount, transfer it into a 1 liter volumetric flask.
5.1.6 Add a small amount of distilled water to the flask and swirl to dissolve.
5.1.7 Then fill up the flask with distilled water until the mark and mix well.
5.2 STANDARDIZATION
5.2.1 Accurately weigh about 200 mg of chelometric standard calcium carbonate, previously dried at 110 for 2 hours and cooled in a desiccator, transfer to a 400-mL beaker, add 10 mL of water, and swirl to form slurry.
5.2.2 Cover the beaker with a watch glass, and introduce 2 mL of diluted hydrochloric acid from a pipet inserted between the lip of the beaker and the edge of the watch glass.
5.2.3 Swirl the contents of the beaker to dissolve the calcium carbonate. Wash down the sides of the beaker, the outer surface of the pipet, and the watch glass with water, and dilute with water to about 100 mL.
5.2.4 While stirring the solution, preferably with a magnetic stirrer, add about 30 mL of the edetate disodium solution from a 50-mL buret. Add 15 mL of sodium hydroxide TS and 300 mg of hydroxy naphthol blue, and continue the titration with the edetate disodium solution to a blue endpoint.
5.2.5 And calculate the morality by the following formula:
(gm CaCO3)(1000)
M= ————————————-
100.9 x ml EDTA

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
Gm Gram
ml Milliliter

9. REVISION HISTORY