The indicator used during the estimation of $COD$ of a water sample is

An aqueous solution of $6.3 \ g$ of oxalic acid dihydrate is made up to $250 \ mL$. The volume of $0.1 \ N \ NaOH$ required to completely neutralise $10 \ mL$ of this solution is.......$mL$

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

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 $HCl$ ...

Consider the titration of $NaOH$ solution versus $1.25\, M$ oxalic acid solution. At the end point,the following burette readings were obtained:
$(i)$ $4.5\, mL$ $\quad (ii)$ $4.5\, mL$ $\quad (iii)$ $4.4\, mL$
$(iv)$ $4.4\, mL$ $\quad (v)$ $4.4\, mL$
If the volume of oxalic acid taken was $10.0\, mL$,then the molarity of the $NaOH$ solution is .... $M$ (Rounded-off to the nearest integer).

Which of the following statements is correct?