In which of the following reactions conc. $\mathrm{H}_2 \mathrm{SO}_4$ is used as an oxidising reagent?
Which of the following statements are true?
In the preparation of $\mathrm{H}_2 \mathrm{SO}_4$ by Contact process, why is $\mathrm{SO}_3$ not absorbed directly in water to form $\mathrm{H}_2 \mathrm{SO}_4$ ?
In Contact process $\mathrm{SO}_3$ is not absorbed directly in water to from $\mathrm{H}_2 \mathrm{SO}_4$ because the reaction is highly exothermic, acid mist is formed. Hence, the reaction becomes difficult to handle.
Note
Write a balanced chemical equation for the reaction showing catalytic oxidation of $\mathrm{NH}_3$ by atmospheric oxygen.
Ammonia $\left(\mathrm{NH}_3\right)$ on catalytic oxidation by atmospheric oxygen in presence of $\mathrm{Rh} / \mathrm{Pt}$ gauge at 500 K under pressure of 9 bar produces nitrous oxide.
Balanced chemical reaction can be written as
$4 \mathrm{NH}_3+\underset{\text { From air }}{5 \mathrm{O}_2}\xrightarrow[500 \mathrm{~K} ; 9 \mathrm{bar}]{\mathrm{Pt} / \text { Rh gauge catalyst }}4 \mathrm{NO}+6 \mathrm{H}_2 \mathrm{O}$
Write the structure of pyrophosphoric acid.
Molecular formula of pyrophosphoric acid is $\mathrm{H}_4 \mathrm{P}_2 \mathrm{O}_7$ and its structure is as follows
