Barium chloride reacts with dilute sulphuric acid to give a yellow precipitate of barium hydroxide.

Which of the following statements is correct?

$\mathrm{A}, \mathrm{B}, \mathrm{C}$ and $\mathrm{D}$ summarise the properties of sulphuric acid depending on whether it is dilute or concentrated. Choose the property $\left(\mathrm{A}, \mathrm{B}, \mathrm{C}, \mathrm{or} \mathrm{D}\right)$, depending on which is relevant to each of the preparations :

$\mathrm{A}$. Dilute acid (typical acid properties)

$\mathrm{B}$. Non-volatile acid

$\mathrm{C}$. Oxidising agent

$\mathrm{D}$. Dehydrating agent

$\left(\mathrm{i}\right)$ Preparation of ethene from ethanol.

The non-volatile acid used to dry hydrogen chloride gas is _____.

$$\begin{gathered} \mathrm{A}: {\mathrm{CH}}_3\mathrm{COOH} \\ \mathrm{B}: \mathrm{Conc}. {\mathrm{H}}_2{\mathrm{SO}}_4 \\ \mathrm{C}: \mathrm{Conc}. {\mathrm{HNO}}_3 \end{gathered}$$

(Enter your correct answer as $\mathrm{A}, \mathrm{B} \mathrm{or} \mathrm{C}$)

A, B, C and D summarise the properties of sulphuric acid depending on whether it is dilute or concentrated. Choose the property (A, B, C or D), depending on which is relevant to each of the preparations (i) to (iii):

A. Dilute acid (typical acid properties)

B. Non- volatile acid

C. Oxidising agent

D. Dehydrating agent

Preparation of copper sulphate from copper oxide.

Complete the following equation:

$2\mathrm{NaCl}+{\mathrm{H}}_2{\mathrm{SO}}_4\left(\mathrm{conc}.\right)\to {\mathrm{Na}}_2{\mathrm{SO}}_4+2$ _____ $\left(\mathrm{g}\right)$.