Page 70 - Pharmaceutical Analytical Chemistry II - Pharm D- 02-06-07102

The titration curves for 0.1 M Ca2+ versus 0.1 M EDTA at pH 7 and pH
10 are shown in the next figure which shows the effect of pH on the
stability constants and correspondingly on the shape of the titration
curves.

pCa

mL EDTA

Metal ion indicators (Metallochromic indicators)

Metal ion indicators are colored organic compounds used to detect
end point in EDTA titration e.g. Eriochrome black T, murexide, xylenol
orange. They are usually dyes which themselves form chelates with metal

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