$10 \, mL$ of concentrated $HCl$ is diluted to $1 \, L$. If $20 \, mL$ of this diluted solution is completely neutralized by $25 \, mL$ of $0.1 \, N$ sodium hydroxide solution,then the normality of the original concentrated hydrochloric acid is:

$8 \ mL$ of $\frac{N}{10} \ HCl$ are required to neutralize $20 \ mL$ of $Na_2CO_3$ solution in water. The normality of the $Na_2CO_3$ solution is: (in $N$)

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

$20 \, mL$ of $0.02 \, M$ hypo solution is used for the titration of $10 \, mL$ of copper sulphate solution,in the presence of excess of $KI$ using starch as an indicator. The molarity of $Cu^{2+}$ is found to be $\times 10^{-2} \, M$ [nearest integer]. Given: $2 Cu^{2+} + 4 I^{-} \rightarrow Cu_{2}I_{2} + I_{2}$ and $I_{2} + 2 S_{2}O_{3}^{2-} \rightarrow 2 I^{-} + S_{4}O_{6}^{2-}$.

Eosin used to detect the end point of precipitation titration by adsorption is called:

Phenolphthalein is used as an indicator for the titration of sodium hydroxide solution against a standard solution of oxalic acid. The colour change that is observed at an alkaline pH close to the equivalence point during this titration is: