Preparation and Standardization of 0.1 M Disodium Edetate (EDTA)

Name: How to Preparare and Standardization of 0.1 M Disodium Edetate (EDTA

Ingredients :

1.Disodium Edetate.
2.Calcium Carbonate
3.Eriochrome black – T
4.Ammonia – Ammonium Chloride Buffer pH10 (Mix 5.4 grams of NH4Cl + 35 milliliters of 10M NH3 solution & dilute to 100 milliliters with water.)
5Hydrochloric Acid.

How to Prepare :

Dissolve 37.2 grams of disodium edetate in enough water to make 1000 milliliters.

How to Standardization:

  • Take about 200 milligrams of dry CaCO3 (previously dried at 110ºC for two hours),
  • Mix it with a little hydrochloric acid.
  • Add 50 milliliters of clean water and 10 to 15 milliliters of Ammonia – Ammonium Hydroxide Buffer.
  • Then, use 0.1M EDTA to test it.
  • The color will change from purple to dark bluish.
  • Each milliliter of 0.1 M EDTA is equivalent to 0.010009 grams of CaCO3.

Calculating the Result:

Weight of CaCO3 (grams) X 0.1 x Amount of CaCO3
Burette Reading x 0.010009 X 100

B.R.: The reading on the Burette in milliliters.

Sources: Indian Pharmacopoeia / United States Pharmacopoeia

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