Rewrite the correct statement with the missing word/s : Aqua regia contains one part by volume of nitric acid and three parts by volume of hydrochloric acid.

Choose the correct answer:

Hydrogen chloride gas being highly soluble in water is dried by :

1. Anhydrous calcium chloride
2. Phosphorous pentaoxide
3. Quick lime
4. Conc. sulphuric acid.

In the laboratory preparation of hydrochloric acid, hydrogen chloride gas is dissolved in water.

(i) Draw a diagram to show the arrangement used for the absorption of HCl gas in water.

(ii) State why such an arrangement is necessary? Give two reasons for the same.

(iii) Write balanced chemical equations for the laboratory preparation of HCl gas when the reactants are :

    (A) below 200°C

    (B) above 200°C

Name two gases which can be used in the study of the fountain experiment. State the common property demonstrated by the fountain experiment ?