$A$ $0.1 \ N$ solution of $Na_2CO_3$ is titrated with $0.1 \ N$ $HCl$ solution. The best indicator to be used is

For an acid-base indicator,the dissociation constant $K_a = 1.0 \times 10^{-5}$. The indicator is red in acidic form and blue in basic form. What is the $pH$ range required for the color change from $80\%$ red to $80\%$ blue?

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

The suitable indicator for the titration of a strong acid and a weak base is:

In base $vs.$ acid titration,at the end point,methyl orange is present as:

$A$ compound '$X$' is a weak acid and it exhibits colour change at $pH$ close to the equivalence point during neutralization of $NaOH$ with $CH_3COOH$. Compound '$X$' exists in ionized form in basic medium. The compound '$X$' is.