EDTA Disodium Salt Molarity/Normality Solutions

EDTA is available as different salts – calcium or sodium – and can be used in many different industrial applications, such as medicinal/pharmaceutical,  agriculture, cosmetics (soap, shampoos), and even as a food additive/preservative.  It was discovered/synthesized in 1935 by Ferdinand Munz, an Austrian chemist.  EDTA is also used in “chelation therapy” , a practice in alternative medicine. It is considered to have some anti-microbial benefits based on some studies.

EDTA standardized solutions (also referred to as titrants) are complexing agents, used when quantifying the concentration of certain metals in aqueous solutions. This titrant is most commonly used in water/wastewater analyses for hardness, typically for calcium and magnesium.

EDTA titrations are pH-dependent. For water hardness a pH of about 10 is ideal. Other metals may call for a different pH environment. A low normality of sodium hydroxide can be used – or, more conveniently – a water hardness buffer.  Combined with an appropriate indicator (hydroxynaphthol blue, calmagite, eriochrome), it will produce a relatively sharp endpoint from which a molarity can be calculated for the metal sample.

EDTA solutions are very stable, and Exaxol guarantees a 1-1/2 year shelf life for most normalities. They are all made/tested in our ISO 17025 laboratory.