Chemistry, asked by abhishekkedare, 1 year ago

write the reaction between edta and magnesium ion in hard water

Answers

Answered by writersparadise
52
EDTA is used to detect the amount of Magnesium and Calcium ions that are present in hard water, sea water etc, by complexometric titration reactions.

EDTA stands for Ethylenediamine tetra-acetic acid. It forms complexes with calcium and magnesium ions which is indicated by the blue indicator Eriochrome Black T (ErioT).

Magnesium ions are allowed to react with excess EDTA during the back titration reactions in which MgCl₂ solution is used. The equation is - 

EDTA⁴⁻ + Mg²⁺ → [Mg-EDTA]²⁻

After the indicator is added, the colour of the solution changes from blue to pink indicating the presence of the ErioT-Mg complexes.
Similar questions