The final acid obtained during the manufacture of $H_2SO_4$ by the contact process is

Which one of the following is most acidic?

In the following,the oxoacid with a peroxy bond is

Discuss the physical and chemical properties of sulphuric acid.

In the following reaction,assign the product of complete hydrolysis at $R.T.$ for the underlined atom:
$\underline{S}OF_4 + H_2O \longrightarrow H_2SO_4 + HF$

Statement $(A)$ Sulphur vapour is paramagnetic. Statement $(B)$ Reaction of dil. $HCl$ with finely divided iron forms $FeCl_3$ and $H_2$ gas. The correct answer is