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Acid-Base Indicator Bromocresol Green Using Spectroscopy

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Acid-Base Indicator Bromocresol Green Using Spectroscopy
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|Acid-Base Indicators: Spectroscopic Method of Determination of Ka |
|Sahib Kaur |
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|3/23/2012 |

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Introduction
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Bromocresol green is a weak organic acid; therefore, it doesn’t reacte to completion, rather it reacts to a dynamic equilibrium, the point at which the rate of reactants turning to products is equal to the rate of products changing back into reactants. An acid (in terms of the bromsted-lowry definition) is a substance that donates H+ ions in a reaction. In bromcresol green, the acidic proton is the that is attached to the SO3- group. The acid, in this lab will be represented by a HB and the conjugate base will be represented by B- . The Ka value for this reaction would

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