Prabin Kalikote

The precautions needed during the laboratory preparation of CO₂ are:
        - The apartus should be made air tight.
        - The Lower end of delivery tube should not touch the solution within the woulfe's bottle.
        - The lower end of thistle funnel should be dipped in the solution.
        - Carbon dioxide is collected in the gas jar by the upward...

The different methods to test the carbon dioxide are:
        - Putting the burning matchstick into the jar containing CO₂. If it extinguishes.
        - When CO₂ is passed through lime water, it turns milky white due to the formation of insoluble CaCo₃. When CO₂ is passed in lime water for long time, the milky color disappears due to the formation of soluble Ca(HCO₃)₂.
        - CO₂ turns...

In the laboratory, carbon dioxide gas is prepared by the reaction of dilute hydrochloric acid with calcium carbonate (limestone or marble).
                                CaCO₃ + 2HCl ----------> CaCl₂ + H₂O + CO₂

When a glass rod is dipped in conc. HCl is brought in contact with ammonia gas, it forms a white fume of ammonium chloride (NH₄Cl).
                            HCl + NH₃ ------------> NH₄Cl

Ammonia gas prepared by heating a mixture of NH₄CL and CA(OH)₂.
                    2NH₄Cl + Ca(OH)₂ ---------> CaCl₂ + 2H₂O + 2NH₃

The uses of ammonia gas are:
        - It is used to manufacture chemical fertilizers.
        - Liquid ammonia is used in refrigerators.
        - It is used to develop blueprint of maps.
        - It is used to make medicines.
        - It is used as laboratory reagent.

Urea is produced when ammonia and carbon dioxide react together at about 1500C under certain pressure (30 atom).
                                2NH₃ + CO₂ ----------> NH₂ - CO - NH₂ + H₂O