Which of the following statement about complexes that form between metal ions and EDTA in aqueous solution is true? Metal-EDTA complexes have an equilibriuma. concentration that is independent of pH.

b Metal-EDTA complexes are stable in acidic . solutions than in basic solutions. c Metal-EDTA complexes are stable in basic solutions than in acidic solutions. d Metal-EDTA complexes are often 2:1 ind. stoichiometry.