Give reasons for the following :
(a) Liquid ammonia is used as a refrigerant in ice plants.
(b) Aqueous solution of ammonia is used for removing grease stains from woollen clothes.
(c) Aqueous solution of ammonia gives a pungent smell.
(d) Aqueous solution of ammonia conducts electricity.
Give reasons for the following :
(a) Liquid ammonia is used as a refrigerant in ice plants.
(b) Aqueous solution of ammonia is used for removing grease stains from woollen clothes.
(c) Aqueous solution of ammonia gives a pungent smell.
(d) Aqueous solution of ammonia conducts electricity.
(a) Liquid ammonia acts as a refrigerant in ice plants. The evaporation of a liquid needs heat energy when liquid ammonia vapourises . It absorbs large quantities of heat without changing its tempurature. For these reasons ammonia is widely used as a refrigerant.
(b) That said, ammonia gas is an alkaline. As such it will saponify oil and grease. The resulting soapy substances will be removed by water. Of course this a simplistic explanation, because there are many different possible interactions between ammonia and lipids, depending on the kind of lipids, temperature, concentration, etc..
(c) Ammonia is a pungent smelling gas.When it is dissolved in water ammonium hydroxide ( aqueous solution of ammonia) is formed. Thus, the pungent smell is due to ammonia gas.
(d) Electricity conduction depends upon presence of ions.
Ammonia gas does not contain ions to conduct electricity while aqueous solution of ammonia i.e. ammonium hydroxide conducts electricity because in solution stage it has ions to move.
NH3(aq)+H2O⇌NH+4(aq)+OH−(aq)
Ammonium hydroxide is a weak electrolyte. Weak electrolytes are partially dissociated to form ions in solution. Those ions in the solution conduct electricity.
(a) Liquid ammonia acts as a refrigerant in ice plants. The evaporation of a liquid needs heat energy when liquid ammonia vapourises . It absorbs large quantities of heat without changing its tempurature. For these reasons ammonia is widely used as a refrigerant.
(b) That said, ammonia gas is an alkaline. As such it will saponify oil and grease. The resulting soapy substances will be removed by water. Of course this a simplistic explanation, because there are many different possible interactions between ammonia and lipids, depending on the kind of lipids, temperature, concentration, etc..
(c) Ammonia is a pungent smelling gas.When it is dissolved in water ammonium hydroxide ( aqueous solution of ammonia) is formed. Thus, the pungent smell is due to ammonia gas.
(d) Electricity conduction depends upon presence of ions.
Ammonia gas does not contain ions to conduct electricity while aqueous solution of ammonia i.e. ammonium hydroxide conducts electricity because in solution stage it has ions to move.
NH3(aq)+H2O⇌NH+4(aq)+OH−(aq)
Ammonium hydroxide is a weak electrolyte. Weak electrolytes are partially dissociated to form ions in solution. Those ions in the solution conduct electricity.
