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A Certain monoprotic acid (weak) serves...

A Certain monoprotic acid (weak) serves as indicator . Assuming that colour change is seen when `1//3^(rd)` of the indicator has been converted to ions and that at end point the pH of solution is 6 , what is the value of `pK_(In)` ?

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To solve the problem, we need to find the value of \( pK_{In} \) for a weak monoprotic acid that serves as an indicator. We know that the color change occurs when one-third of the indicator has been converted to its ionized form, and at the endpoint, the pH of the solution is 6. ### Step-by-Step Solution: 1. **Understanding the Indicator Reaction**: The weak acid (indicator) can be represented as \( HIn \) which dissociates into \( H^+ \) and \( In^- \): \[ HIn \rightleftharpoons H^+ + In^- ...
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Acid-base indicators are either weak organic acids or weak organic bases. Indicator change colour in dilute solution when the hydonium ion concentration reaches a particular calur For example. Phenolphthalein is a coloureless stbstance in any aqueous solution with a pH less than 8.3 In between the pH range 8.3 to 10, transition of colour (colourless to pink ) takes place and if pH of solution is greater than 10 solution is dark pink. Considering an acid indicator Hln, the equilibrium involving it and its conjgate base In^(-) can be represented as : " " underset("acidic from")(HIn)hArrH^(+)underset("basic from")(In^(-)) pH of solution can be computed as : " " pH=pK_(In)+log.([IN^(-)])/([HIn]) In general, transition of colour takes place in between the pH range pK_(In+-1. An indicator is a weak acid and pH range is 4.0 to 6.0. If indicator in 50% ionized in a given solution then what is the inization constant of the acid ?

Acid-base indicators are either weak organic acids or weak organic bases. Indicator change colour in dilute solution when the hydonium ion concentration reaches a particular calur For example. Phenolphthalein is a coloureless stbstance in any aqueous solution with a pH less than 8.3 In between the pH range 8.3 to 10, transition of colour (colourless to pink ) takes place and if pH of solution is greater than 10 solution is dark pink. Considering an acid indicator Hln, the equilibrium involving it and its conjgate base In^(-) can be represented as : " " underset("acidic from")(HIn)hArrH^(+)underset("basic from")(In^(-)) pH of solution can be computed as : " " pH=pK_(In)+log.([IN^(-)])/([HIn]) In general, transition of colour takes place in between the pH range pK_(In+-1. Calculate the pH at equivalence point when 5 milli mol of HB is titrated with 0.1 M NaOH.

Acid-base indicators are either weak organic acids or weak organic bases. Indicator change colour in dilute solution when the hydonium ion concentration reaches a particular colour For example. Phenolphthalein is a coloureless substance in any aqueous solution with a pH less than 8.3 In between the pH range 8.3 to 10, transition of colour (colourless to pink ) takes place and if pH of solution is greater than 10 solution is dark pink. Considering an acid indicator Hln, the equilibrium involving it and its conjgate base In^(-) can be represented as : " " underset("acidic from")(HIn)hArrH^(+)underset("basic from")(In^(-)) pH of solution can be computed as : " " pH=pK_(In)+log.([IN^(-)])/([HIn]) In general, transition of colour takes place in between the pH range pK_(In+-1 Which of the following indicator is most suitable for titration of HB with strong base :

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Acid-base indicators are either weak organic acids or weak organic bases. Indicator change colour in dilute solution when the hydonium ion concentration reaches a particular calur For example. Phenolphthalein is a coloureless stbstance in any aqueous solution with a pH less than 8.3 In between the pH range 8.3 to 10, transition of colour (colourless to pink ) takes place and if pH of solution is greater than 10 solution is dark pink. Considering an acid indicator Hln, the equilibrium involving it and its conjgate base In^(-) can be represented as : " " underset("acidic from")(HIn)hArrH^(+)underset("basic from")(In^(-)) pH of solution can be computed as : " " pH=pK_(In)+log.([IN^(-)])/([HIn]) In general, transition of colour takes place in between the pH range pK_(In+-1. Select the correct statement (s) :