For the indicator 'Hin' the ratio `(Ind^(Θ))//(HIn)` is `7.0` at `pH` of `4.3`. What is `K_(eq)` for the indicator.

Hin is an acidic indicator (K_(Ind) =10^(-7)) which dissociates into aqueous acidic solution of 30mL of 0.05M H_(3)PO_(4) (K_(1) = 10^(-3), K_(2) = 10^(-7), K_(3) = 10^(-13)) If Hin and Ind^(Theta) posses colour P and Q , respectively, and concentration of HIn is 120 times than that of Ind^(Theta) . colour Q predominates over P when concnetration of Ind^(Theta) is 127 times of HIn . What is the pH range of the indicator.

Hin is an acidic indicator (K_(Ind) =10^(-7)) which dissociates into aqueous acidic solution of 30mL of 0.05M H_(3)PO_(4) (K_(1) = 10^(-3), K_(2) = 10^(-7), K_(3) = 10^(-13)) If Hin and Ind^(Theta) posses colour P and Q , respectively, and concentration of HIn is 120 times than that of Ind^(Theta) . colour Q predominates over P when concnetration of Ind^(Theta) is 127 times of HIn . What is the pH range of the indicator.

The human eye is sensitive to colour differences of indicator only when the ratio [In^(-) ] // [Hin] is greater then 10 (or) smaller than 0.1. What should be the minimum change in the pH of solution of observe a complete colour change . (pK_(In) =5) .

For the indicator thymol blue, pH is 2.0 when half of the indicator is in unionised form. Find the % of indicator in unionised form in a solution with [H^(+)]=4xx10^(-3)M .

Select the correct set of the statements for an acid type indicator used in a titration : (i) In general, pH range of an indicator is (pK_(a)-1) to (pK_(a)+1) and indicator shows its characteristic colours in this range. (ii) In general pH range of an indicator is (pK_(a)-1) to (pK_(a)-1) and indicator does not show its characteristic colours in this range (iii) In this relation : pH=pK_(In) +log_(10)((["In"^(-)])/(["HIn"])),pH value representes pH of indicator solution. (iv) In this relation : pH=pK_(In) +log_(10)((["In"^(-)])/(["HIn"])),pH value represents pH of resulting solution containing indiactor .

An acid base indicator has K_(HIn)=3.0xx10^(-5) . The acid from of the indicator is red and the basic form is blue the change in (H^(+)) required to change the indicator from 75% red to 75%blue is :-