Product Overview

EDTA Disodium Salt 99% AR/ACS (CAS No. 6381-92-6) is the disodium salt dihydrate of ethylenediaminetetraacetic acid, a multidentate complexing reagent that forms stable chelate structures with many divalent and trivalent metal ions. Its metal-binding response is strongly influenced by pH because progressive deprotonation of the ligand changes the proportion available for coordination. This behaviour is fundamental to conventional complexometric analysis.

The AR/ACS grade is intended for preparation of analytical EDTA solutions, complexometric titrations and metal-ion masking procedures. It is particularly relevant to determinations of calcium and magnesium, water-hardness analysis and other wet-chemical methods in which a controlled chelating reagent is required. The grade supports analytical reagent preparation, method verification and routine quality-control work using suitable buffers, indicators and solution standardisation procedures.

Typical Applications

• Preparation and standardisation of EDTA titrant solutions
• Determination of total hardness in water
• Combined determination of calcium and magnesium
• Complexometric determination of compatible metal ions
• Masking of interfering metal ions in analytical procedures
• Preparation of metal–EDTA working solutions
• Laboratory verification of complexometric titration methods

Common Synonyms

• Ethylenediaminetetraacetic acid disodium salt dihydrate
• Disodium ethylenediaminetetraacetate dihydrate
• Disodium EDTA dihydrate
• Disodium edetate dihydrate
• EDTA disodium salt dihydrate
• Na₂H₂EDTA dihydrate

Storage Conditions

Keep the container tightly sealed and protect the reagent from contamination and uncontrolled moisture exchange. Use clean sampling equipment to preserve the dihydrate form and prevent introduction of metal ions that could influence analytical blanks or titration response.