Identify the correct order of acidity of hydrides of $16^{th}$ group elements from the following.

The incorrect statement$(s)$ about $O_3$ is (are):

$A$ sulphate of a metal $(A)$ on heating evolves two gases $(B)$ and $(C)$ and an oxide $(D).$ Gas $(B)$ turns $K_2Cr_2O_7$ paper green while gas $(C)$ forms a trimer in which there is no $S-S$ bond. Compound $(D)$ with $HCl$ reacts to form a compound $(E)$ which exists as a dimer. Compounds $(A)$,$(B)$,$(C)$,$(D)$ and $(E)$ are respectively:

Sulphur trioxide can be obtained by which of the following reactions?

Which of the following has an $S-S$ bond?

Which of the following oxides of sulfur contains a sulfur-sulfur $(S-S)$ bond?