Question

Give an example of the following chemical reaction which involves-

(a) Two gases combine to form a white solid.

(b) Two solids combine to form a liquid.

Answer 1

(a) Two gases combine to form a white solid

• Ammonia gas reacts with hydrogen chloride gas to form solid ammonium chloride.

$$\begin{gathered} {\mathrm{NH}}_3\left(\mathrm{g}\right)+\mathrm{HCl}\left(\mathrm{g}\right)\rightleftharpoons {\mathrm{NH}}_4\mathrm{Cl}\left(\mathrm{s}\right) \\ \mathrm{Ammonia}\mathrm{Hydrogen}\mathrm{chloride}\mathrm{Ammonium}\mathrm{chloride} \end{gathered}$$

(b) Two solids combine to form a liquid

• Carbon and sulphur both are solid and on heating together they form carbon disulphide which is in a liquid state.

$$\begin{gathered} \mathrm{C}\left(\mathrm{s}\right)+2\mathrm{S}\left(\mathrm{s}\right)\stackrel{∆}{\to }{\mathrm{CS}}_2\left(\mathrm{l}\right) \\ \mathrm{Carbon}\mathrm{sulphur}\mathrm{Carbon}\mathrm{disulphide} \end{gathered}$$