Bleaching action of chlorine is due to

What are $X$ and $Y$ in the given reactions?
$2X_{2(g)} + 2H_2O_{(l)} \to 4H^{+}_{(aq)} + 4X^{-}_{(aq)} + O_{2(g)}$
$Y_{2(g)} + H_2O_{(l)} \to HY_{(aq)} + HOY_{(aq)}$

When a mixture of solid $NaCl$ and solid $K_2Cr_2O_7$ is heated with concentrated $H_2SO_4$,orange-red vapours are evolved. These vapours are of which compound?

Which of the following halides is inert towards hydrolysis at room temperature?

Which of the following are correct matches?
$(a)$ $ClO_4^- > ClO_3^- > ClO_2^- > ClO^-$ (Stability order)
$(b)$ $Cl_2 > Br_2 > F_2 > I_2$ (Bond energy)
$(c)$ $OF_2 < OH_2 < OCl_2$ (Bond angle)
$(d)$ $I^- > Br^- > Cl^-$ (Reducing power)

Which of the following is not a characteristic of interhalogen compounds?