3. The colour changes corresponding to the pH intervals for the three indicatorsare given in the following table:-Colour changeRed to orangepH Interval3 - 56 - 88 - 10IndicatorsMethyl orangeBromothymol bluePhenolphthaleinYellow to blueColourless to pinkComment on the end-point reached by using different indicators in Part 3.1.3 andPart 3.1.4. Confirm the suitability of each indicator by referring to the pH curvesdetermined in this experiment.

So according to the given data and the indicator we have the following conclusion. :

3. The colour changes corresponding to the pH intervals for the three indicators are given in the following table:- Colour change Red to orange Yellow to blue Colourless to pink pH Interval 3 -5 Indicators Methyl orange Bromothymol blue Phenolphthalein 6 - 8 8 - 10 Comment on the end-point reached by using different indicators in Part 3.1.3 and Part 3.1.4. Confirm the suitability of each indicator by referring to the pH curves determined in this experiment.

3. The colour changes corresponding to the pH intervals for the three indicators are given in the following table:- Colour change Red to orange Yellow to blue Colourless to pink pH Interval 3 -5 Indicators Methyl orange Bromothymol blue Phenolphthalein 6 - 8 8 - 10 Comment on the end-point reached by using different indicators in Part 3.1.3 and Part 3.1.4. Confirm the suitability of each indicator by referring to the pH curves determined in this experiment.

Principles of Instrumental Analysis

7th Edition

ISBN:9781305577213

Author:Douglas A. Skoog, F. James Holler, Stanley R. Crouch

Publisher:Douglas A. Skoog, F. James Holler, Stanley R. Crouch

Chapter13: An Introduction To Ultraviolet-visible Molecular Absorption Spectrometry

Section: Chapter Questions

Problem 13.11QAP: The equilibrium constant for the conjugate acid-base pair HIn+H2OH3O++In is 8.00 10-5. From the...

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