Methyl orange is an indicator in acid-alkali titration. It gives

Phenolphthalein is not suitable for the titration of

The indicator used in the titration of $Na_2CO_3$ with $HCl$ is..................

For an acid indicator with $K_{in} = 1.0 \times 10^{-5}$, the color change occurs when the concentration of the indicator is $1 \times 10^{-3} \ M$. Find the $pH$ at which the color change occurs.

If we use phenolphthalein as an indicator in a titration of $Na_2CO_3$ with $HCl$,the usual result is:

The rapid change of $pH$ near the stoichiometric point of an acid-base titration is the basis of indicator detection. The $pH$ of the solution is related to the ratio of the concentrations of the conjugate acid $(HIn)$ and base $(In^{-})$ forms of the indicator by the expression: