Identify the element having the highest density from the following.

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

Write the conditions to maximize the yield of $H_2SO_4$ by Contact process.

Which of the following are peroxo acids of sulphur?

Which of the following statements is $INCORRECT$?

Identify the correct statements from the following:
$i$. Sulphuric acid is manufactured by contact process.
$ii$. $SO_3$ dissolves in $H_2SO_4$ to form pyrosulphuric acid $(H_2S_2O_7)$.
$iii$. $H_2SO_4$ is used in the manufacture of fertilisers such as ammonium sulphate and super phosphate.
$iv$. In the reaction,$S + 2H_2SO_4 (\text{conc.}) \longrightarrow 3SO_2 + 2H_2O$,$H_2SO_4$ is oxidised to $SO_2$.