A student added 25.0 uL of a solution of magnesium chloride to a microcentrifuge tube along with a color changing indicator, and titrated with 1.00 x 10−2 M EDTA to the endpoint. The color change occurred at 21.3 uL. What was the [Mg2+]?
The accuracy of an indicator’s end point depends on the relative strength of the metal–indicator complex and the metal.Unfortunately, because the indicator is a weak acid, the color of the uncomplexed indicator also changes with pH.
