Which of the following compounds is $NOT$ in the gaseous phase at $25^{\circ} C$?

Which of the following is the correct increasing order of the reducing power of halide ions?

With respect to hypochlorite,chlorate,and perchlorate ions,choose the correct statement$(s)$.
$A.$ The hypochlorite ion is the strongest conjugate base.
$B.$ The molecular shape of only the chlorate ion is influenced by the lone pair of electrons on $Cl$.
$C.$ The hypochlorite and chlorate ions disproportionate to give rise to an identical set of ions.
$D.$ The hypochlorite ion oxidizes the sulfite ion.

Which of the following decreases down the halogen group?

What is the reason for the bleaching action of chlorine?

Identify a compound having highest thermal stability.