In the titration of a strong acid and a weak base,the indicator used is:

$10.0 \, mL$ of $0.05 \, M \, KMnO_4$ solution was consumed in a titration with $10.0 \, mL$ of given oxalic acid dihydrate solution. The strength of given oxalic acid solution is $..... \times 10^{-2} \, g / L$ (Round off to the nearest integer).

Solution $X$ contains $Na_2CO_3$ and $NaHCO_3$. $20 \ mL$ of $X$ when titrated using methyl orange indicator consumed $60 \ mL$ of $0.1 \ M \ HCl$ solution. In another experiment,$20 \ mL$ of $X$ solution when titrated using phenolphthalein consumed $20 \ mL$ of $0.1 \ M \ HCl$ solution. The concentrations (in $mol \ L^{-1}$) of $Na_2CO_3$ and $NaHCO_3$ in $X$ are respectively:

The indicator used in the titration of $Na_2CO_3$ with $H_2SO_4$ is

The strength of an aqueous $NaOH$ solution is most accurately determined by titrating it against a standard solution of oxalic acid. (Note: consider that an appropriate indicator is used)

In the titration of $I_{2(aq)}$ by $S_2O_3^{2-}{_{\text{(aq)}}}$ using the starch indicator, the end point is indicated by: