chapter 7.  ELEMENTS OF GROUPS 16, 17 AND 18 class 12 chemistry textbook solution

Answer:-

a. Action of Hydrochloric Acid (HCl) on Ammonia (NH3):

When hydrochloric acid (HCl) reacts with ammonia (NH3), it forms ammonium chloride (NH4Cl), a salt. The reaction can be represented as follows:

NH3(g) + HCl(g) → NH4Cl(s)

In this reaction, ammonia, which is a weak base, reacts with hydrochloric acid, which is a strong acid, to produce ammonium chloride. The ammonia molecule donates a lone pair of electrons to the hydrogen ion (H+) from hydrochloric acid, resulting in the formation of ammonium ions (NH4+) and chloride ions (Cl-). The chloride ions combine with the ammonium ions to form solid ammonium chloride (NH4Cl), which may precipitate out if the reaction is carried out in a concentrated solution.

This reaction is often used to prepare ammonium chloride in the laboratory and is also a common way to remove ammonia gas from a gaseous mixture.

b. Action of Hydrochloric Acid (HCl) on Sodium Carbonate (Na2CO3):

When hydrochloric acid reacts with sodium carbonate, it results in the formation of sodium chloride (NaCl), carbon dioxide (CO2) gas, and water (H2O). The chemical equation for this reaction is as follows:

Na2CO3(s) + 2HCl(aq) → 2NaCl(aq) + CO2(g) + H2O(l)

In this reaction, hydrochloric acid reacts with sodium carbonate to produce sodium chloride, carbon dioxide, and water. The sodium carbonate (Na2CO3) is a salt composed of sodium ions (Na+) and carbonate ions (CO3^2-). The hydrochloric acid (HCl) provides hydrogen ions (H+) in solution. The reaction proceeds as follows:

1. HCl reacts with the carbonate ion (CO3^2-) to produce carbon dioxide gas (CO2).
2. The sodium ions (Na+) from sodium carbonate combine with chloride ions (Cl-) from hydrochloric acid to form sodium chloride (NaCl), which remains in solution.
3. Water (H2O) is also produced as a product of the reaction.

The release of carbon dioxide gas in this reaction can be observed as effervescence or bubbling. This reaction is commonly used to prepare carbon dioxide gas in the laboratory and is also employed in various industrial processes.