The correct order of acidity of $HClO$, $HBrO$, and $HIO$ is

Concentrated $H_2SO_4$ cannot be used to prepare $HBr$ from $NaBr$,because it

Sulphur dioxide on reaction with chlorine in the presence of charcoal gives compound $(A)$. This on reaction with white phosphorus gives $SO_2$ and compound $(B)$. The correct statement about '$B$' is

Which of the following oxoacids of chlorine is the least oxidizing in nature?

Among the following oxoacids,the correct decreasing order of acid strength is:

Which one will liberate $Br_2$ from $KBr$?