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Chemistry Forums for Students => High School Chemistry Forum => Topic started by: key_i on November 22, 2006, 05:45:40 AM

Title: About complexometric titration
Post by: key_i on November 22, 2006, 05:45:40 AM

i would like to ask why hydroxynaphthol blue indicator instead of eriochrome Black T is used in determining the conc. of Ca2+ ion (only Ca ions).

Title: Re: About complexometric titration
Post by: Albert on November 22, 2006, 02:01:41 PM

Because the complex calcium-eriochrome isn't very stable (log K_f=5.5).