6. EDTA titrations of metal ions are pH sensitive. Which statements are TRUE?
(1) At low pH, the amount of EDTA in the form Y4- decreases.(2) As the pH is lowered, the end point becomes less distinct.
(3). Metals with higher formation constants cannot be titrated at lower pH.
(4) All metal ions require alkaline titration conditions.
(5) At higher pH values, the metal hydroxide might precipitate.
Your answer:
(A) (1), (2) and (5);
(B) (2) and (4);
(C) (2),(3) and (4);
(D) (1), (2) and (4);
(E) The statements are all true.