Q. When EDTA solution is added to ${Mg}^{2 +}\$ion solution, then which of the following statements is not true?
A) Four coordinate sites of ${Mg}^{2 +}$ are occupied by EDTA and remaining two sites are occupied by water molecules.
B) All six coordinate sites of ${Mg}^{2 +}$ are occupied.
C) $P^{H}$ of the solution is decreased.
D) Colourless $\lbrack Mg - EDTA\rbrack^{2 -}$chelate is formed.
Explanation
(a)
$\left\lbrack H_{2}EDTA \right\rbrack^{2 -} + Mg^{2 +} \rightarrow \lbrack MgEDTA\rbrack^{2 +} + 2H^{+}$
In this complex, four donor sites are occupied by oxygen and two donor sites are occupied by nitrogen.
This complex is six coordinated.
Complex $\lbrack MgEDTA\rbrack^{2 -}$ is colourless.
Increase in $\lbrack H^{+}\rbrack$decreases pH of the solution.
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.