Which of the following statements is correct?

Chlorine reacts with sodium hydroxide under various conditions to give:

In the production of $UF_6$ required for the enrichment of ${}^{235}U$,which of the following is used?

$X_2$ is used in the refining of $Ti$ metal by the van Arkel method. $Y_2$ does not liberate $O_2$ from water and does not form $HY$ and $HOY$ with water. $X_2$ and $Y_2$ are respectively:

The correct statement$(s)$ regarding $(i) HClO$,$(ii) HClO_2$,$(iii) HClO_3$,and $(iv) HClO_4$ is(are):
$(A)$ The number of $Cl=O$ bonds in $(ii)$ and $(iii)$ together is two.
$(B)$ The number of lone pairs of electrons on $Cl$ in $(ii)$ and $(iii)$ together is three.
$(C)$ The hybridization of $Cl$ in $(iv)$ is $sp^3$.
$(D)$ Amongst $(i)$ to $(iv)$,the strongest acid is $(i)$.

Which one of the following is a pseudohalide?