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| Properties of Ammonia |
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 Colourless |
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Strong pungent smell |
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Slight alkaline taste |
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Non-poisonous Fatal in large doses |
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Lighter than air - V.D=8.5 |
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Highly soluble in water |
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Easily liquefied at low temp |
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Liquid ammonia boils at -33.5ºC |
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Solid ammonia melts at -77.7ºC |
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| Combustibility |
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| Ammonia is neither combustible nor a supporter of combustion. |
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| Reaction with Oxygen |
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Ammonia burns in oxygen forming N2 and water |
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Ammonia is oxidized to nitric oxide when ammonia-oxygen mixture is passed over heated platinum. The catalytic oxidation of ammonia is an exothermic reaction. |
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| Reaction with water |
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An aqueous solution of ammonia is basic in nature. It turns red litmus blue and phenolphthalein solution pink. |
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| NH3 + H2O
g NH4OH |
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An aqueous solution of ammonia in water is called liquor ammonia. Fortis. |
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The aqueous solution of ammonia undergoes partial dissociation to give hydroxyl ions. |
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Ammonia in gaseous form or in aqueous solution, neutralizes acids forming respective ammonium salts. |
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| NH3 + HCl
g NH4Cl |
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| NH4OH+ HCl
g NH4Cl + H2O |
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The aqueous solution of ammonia precipitates hydroxides of metals from the solution of their salts. |
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The precipitates vary in color and solubility and hence ammonium hydroxide is used in the qualitative analysis for identifying cations. |
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| Reducing nature |
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Ammonia gas is a strong reducing agent and reduces heated metallic oxides to metals. |
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Ammonia reduces chlorine to hydrogen chloride. This HCl further combines with excess ammonia forming NH4Cl |
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Ammonia [in excess] |
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Chlorine [ In excess ] |
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Ammonia solutions are used to clean, bleach, and deodorize; to etch aluminum; to saponify (hydrolyze) oils and fats; and in chemical manufacture. |
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Ammonia is also used in large amounts in the Ostwald process for the synthesis of nitric acid; in the Solvay process for the synthesis of sodium carbonate; in the synthesis of numerous organic compounds used as dyes, drugs, and in plastics; and in various metallurgical processes. |
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The ammonia sold for household use is a dilute water solution of ammonia in which ammonium hydroxide is the active cleansing agent. |
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As a constituent of smelling salt, it revives a fainted person. But it should be used with caution since it can attack the skin and eyes. The vapors are especially irritating prolonged exposure and inhalation cause serious injury and may be fatal. |
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Ammonia and its compounds are mainly used as fertilizers. |
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Liquid ammonia is used as refrigirant. |
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