Which of the following molecules exhibits the highest acidic nature?

What is $Oleum$?

Identify the $FALSE$ statement from the following.

What is true about $H_2S_nO_6$ (Polythionic acid)?

Among the following allotropic forms of sulphur,the number of allotropic forms,which will show paramagnetism is ..... .
$(A)$ $\alpha$-sulphur
$(B)$ $\beta$-sulphur
$(C)$ $S_2$-form

Describe the manufacture of $H_2SO_4$ by the contact process.