As the atomic number of halogens increases,the halogens

As the atomic number of halogens increases,the halogen.......

$Cl_{2(g)} + Ba(OH)_2 \to X (aq.) + BaCl_2 + H_2O$
$X + H_2SO_4 \to Y + BaSO_4$
$Y \xrightarrow[\Delta > 365 \ K]{\Delta } Z + H_2O + O_2$
$Y$ and $Z$ are respectively

Which among the following is used as an oxidizing agent to bleach wood pulp into white paper?

Select the correct set of species which cannot react with water but react with $NaOH$:
$(i) \, NO_2$ $(ii) \, P_4$ $(iii) \, Al$ $(iv) \, I_2$

Concentrated $HNO_3$ reacts with iodine to give: