Eriochrome Black T Color Range: Find It Here

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The discussion focuses on the color range of the indicator Eriochrome Black T, highlighting its color changes at different pH levels. At pH 6.3, it appears red (H2Ind-), transitioning to blue at pH 11.5 (HInd--) and yellow-orange in its fully deprotonated form (Ind---). The reaction with Mg2+ results in a wine-red color before the endpoint, which occurs between pH 6.6 and 10.5 when titrating with EDTA. To enhance the visibility of the color change, adding methyl red is suggested, which shifts the color from red to green at the endpoint. Understanding these color transitions is crucial for accurate titration results.
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any one know where I can find the colour range of the indicator Eriochrome black T?
 
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H2Ind- (red) pH=6.3 HInd-- (blue) pH=11.5 Ind--- (yellow-orange)

Mg2+ + HInd-- double arrow MgInd- + H+ wine-red colour before EP buffer pH 6.6-10.5 (NH4Cl/NH3) further titration with EDTA around EP MgInd- (wine-red) + HY--- double arrow MgY-- + HInd-- (blue). It is not easy to see the colour change but it can made better by adding methylred (pH 6.6-10.5) it is yellow and forms with the blue green at the EP point, the change is than from red to green.
 
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