$10.0 \, mL$ of $Na_{2}CO_{3}$ solution is titrated against $0.2 \, M \, HCl$ solution. The following titre values were obtained in $5$ readings.
$4.8 \, mL, 4.9 \, mL, 5.0 \, mL, 5.0 \, mL$ and $5.0 \, mL$
Based on these readings,and convention of titrimetric estimation,the concentration of $Na_{2}CO_{3}$ solution is .... $mM$.
(Round off to the nearest integer)

Can titrations with $KMnO_4$ be performed in the presence of $HCl$? Why?

The indicator used in the titration of iodine against sodium thiosulphate is

Which reagent is commonly used for the determination of water hardness by titration?

$20 \, mL$ of calcium hydroxide was consumed when it was reacted with $10 \, mL$ of an unknown solution of $H_2SO_4$. Also,$20 \, mL$ of a standard solution of $0.5 \, M$ $HCl$ containing $2$ drops of phenolphthalein was titrated with calcium hydroxide. The mixture showed a pink color when the burette displayed the value of $35.5 \, mL$,whereas the burette showed $25.5 \, mL$ initially. The concentration of $H_2SO_4$ is $..........M$ (Nearest integer).

The amount of oxalic acid in a solution can be determined by titration with $KMnO_4$ in the presence of $H_2SO_4$. If the titration is performed in the presence of $HCl$,the results are unsatisfactory because $HCl$ ...