What Happens to the Reaction of Alkali with Ammonium Salt
Principle: Generally, ammonia can be prepared by heating an ammonium salt with any alkali. Ammonia is prepared in the laboratory by heating ammonium chloride and quick lime (CaO) or slaked lime [Ca(OH)2].
Chemical Reaction: 2NH4Cl+CaO = 2NH3+CaCl2+H2O or 2NH4Cl+Ca(OH)2 = 2NH3+CaCl2+H2O
Ammonia is highly soluble in water and cannot be collected by water removal. Ammonia is lighter than air. Hence it is collected by the downward removal of air.
Necessary Materials: A heat-resistant kettle, several gas jars, an exhaust tube bent at right angles, two test rods, a container, a Bunsen Burner, cork, mortar pestle, and test tube.
Chemicals Required: Ammonium chloride (NH4Cl), quick lime, or calcium oxide (CaO).
How to do the Reaction of Alkali with Ammonium Salt
1. Mix well some dry ammonium chloride and about double the weight of dry lime in a mortar and bring the mixture to a large heatproof glass tube.
2. Keep the glass tube horizontal with a holder.
3. Attach an exhaust pipe bent at right angles to the mouth of the glass tube.
4. The open end of the exhaust tube is inserted into an overhanging dry gas jar.
5. Attach the gas jar to a rod with the holder in advance.
6. Now slowly apply heat to the glass tube with the help of a Bunsen Burner. Foul-smelling ammonia gas is evolved and the gas accumulates in the jar by the downward removal of air.
7. To check whether the gas jar is full of ammonia, hold a glass rod dipped in HCl over the mouth of the gas jar. If thick white fumes are produced, the gas jar is full of ammonia.
8. Close the mouth of the aerated jar with a lid and keep it on the table.
9. Similarly collect ammonia gas in some gas jars
Now we observe the reaction that happens
| Experiments | Observations | Decisions |
|---|---|---|
| 1. Fill a dry test tube with ammonia and note its color and smell. | 1. No color, but get a squishy smell | 1. Ammonia is a colorless gas with a pungent odor |
| 2. (a) Fill a test tube with ammonia and hold the mouth of it with the thumbs and push the test tube up and immerse the mouth of the test tube with the thumbs in water, then remove the finger. | (a) Water rushes into the tube and fills the tube completely. | (a) Ammonia gas is highly soluble in water. |
| 2. (b) A test tube filled with ammonia gas and a wet red litmus paper inserted inside it. | (b) Red litmus paper turned blue. | (b) Ammonia gas is alkaline. NH3+H2O=NH4OH. |
| 2. (c) Add ammonia gas to the test tube and insert the wet yellow paper into it. | (c) Yellow paper turned brown. | (c) Ammonia was detected. |
| 3. Insert a burning stick into an ammonia-filled gas jar. | 3. The stick went out and the gas did not burn. | 3. Ammonia gas is not flammable and does not aid in combustion. |
| 4. Place an air-filled gasser over the mouth of an ammonia gasser and remove the lid between them. After some time red litmus paper soaked in water is inserted into the upper jar. | 4. Red litmus paper turns blue. | 4. Ammonia is lighter than air. Because the ammonia in the lower jar displaces the air in the upper jar and takes its place. |
| 5. Hold a glass rod soaked in hydrochloric acid over the mouth of a test tube or gas jar full of ammonia. | 5. The mouth of the test tube or gasser is filled with white fumes. | 5. Ammonia reacts with hydrochloric acid to produce white fumes of ammonium chloride. HCL+NH3 = NH4Cl |
Conclusion:
We observe the experiment to the Reaction of Alkali with Ammonium Salt it finally produces Ammonia Gas.
