The chemical formula of oleum is ${\mathrm{H}}_2{\mathrm{S}}_2{\mathrm{O}}_5$.

Identify the substance underlined in the following:

The acid that is a dehydrating as well as a drying agent.

Complete the following equation:

$\mathrm{C} + \mathrm{conc}. {\mathrm{H}}_2{\mathrm{SO}}_4\to$

Match List-I with List-II :

 Choose the correct answer from the options given below:

Name the acid used for the preparation of hydrogen chloride gas in the laboratory. Why is this particular acid preferred to other acids?

Which property of sulphuric acid is shown by the reaction of concentrated sulphuric acid with carbon?

Explain the following with the help of balanced chemical equation:

Dehydration of formic acid by concentrated ${\mathrm{H}}_2{\mathrm{SO}}_4$

Give reason :

Conc. ${\mathrm{H}}_2{\mathrm{SO}}_4$ is a good dehydrating agent.

Which of the following statements is correct?