At what pH will an indicator with K_b = 1 tim | vedclass

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

Question

(B) For a basic indicator,the equilibrium is represented as: $InOH \rightleftharpoons In^+ + OH^-$. The dissociation constant is $K_b = \frac{[In^+][O

Vedclass · Accepted Answer

$3$

Vedclass · Answer

(B) For a basic indicator,the equilibrium is represented as: $InOH ightleftharpoons In^+ + OH^-$. The dissociation constant is $K_b = \frac{[In^+][OH^-]}{[InOH]}$. The color change occurs when $[In^+] = [InOH]$,which implies $K_b = [OH^-]$. Given $K_b = 1 	imes 10^{-11}$,we have $[OH^-] = 1 	imes 10^{-11} \ M$. Now,$pOH = -\log[OH^-] = -\log(1 	imes 10^{-11}) = 11$. Since $pH + pOH = 14$,we get $pH = 14 - 11 = 3$.

At what $pH$ will an indicator with $K_b = 1 \times 10^{-11}$ show a color change in a $1 \times 10^{-4} \ M$ solution?

Similar Questions

Which indicator is used for the titration of a weak acid (oxalic acid) and a strong base (caustic soda)?

Which indicator works in the $pH$ range of $8 - 9.8$?

Which indicator is used for the titration of $CH_3COOH$ and $NaOH$?

$20 \ mL$ of $0.5 \ N \ HCl$ and $35 \ mL$ of $0.1 \ N \ NaOH$ are mixed. The resulting solution will

Starch can be used as an indicator for the detection of traces of

Vedclass Test Series

Exam Paper Generator

Online Exam Module