Physical and chemical properties

Chemical formula: NH4Cl

Electronic:

Relative molecular mass: 53.49

Character

Colorless crystal or white granular powder, it is a kind of strong electrolyte, which dissolves in water and ionizes to produce ammonium ions and chloride ions. When ammonia gas and hydrogen chloride combine to form ammonium chloride, there will be white smoke. Odorless. The taste is salty, cool and slightly bitter. It has low hygroscopicity, but it can also absorb moisture and agglomerate in wet and rainy weather. Powdered ammonium chloride is very easy to deliquesce, especially qualified products. The moisture absorption point is generally around 76%. When the relative humidity in the air is greater than the moisture absorption point, ammonium chloride will absorb moisture and easily agglomerate. Capable of sublimation (actually the process of decomposition and regeneration of ammonium chloride) without melting point. The relative density is 1.5274. The refractive index is 1.642. Low toxicity, median lethal dose (rat, oral) 1650mg/kg. irritating. Heating to 350 ° C sublimation, the boiling point of 520 ° C.

Soluble in water, slightly soluble in ethanol, soluble in liquid ammonia, insoluble in acetone and ether. Hydrochloric acid and sodium chloride can reduce its solubility in water. Its solubility in water is 29.4g at 0°C, 33.2g at 10°C, 37.2g at 20°C, 41.4g at 30°C, 45.8g at 40°C, and 45.8g at 50°C. 50.4g at 60°C, 55.3g at 60°C, 60.2g at 70°C, 65.6g at 80°C, 71.2g at 90°C, and 77.3g at 100°C). It begins to decompose when heated to 100°C, and can be completely decomposed into ammonia gas and hydrogen chloride gas at 337.8°C. When it is cooled, it will recombine to form ammonium chloride with extremely small particles and appear as white smoke, which is not easy to sink and is extremely difficult to regenerate. Dissolve in water.

The pH of the aqueous solution: Because the ammonium ion ionized in the water is hydrolyzed to make the solution acidic, the pH value of the saturated ammonium chloride solution at room temperature is generally around 5.6. At 25°C, 1% is 5.5, 3% is 5.1, and 10% is 5.0. Ammonium chloride itself can be used as a stable reagent for bismuth and antimony (provide chloride ions for coordination, and its compound and ammonium chloride are co-dissolved in dilute hydrochloric acid when used).

chemical properties

The aqueous solution is weakly acidic, and the acidity increases when heated. It is corrosive to ferrous metals and other metals, especially to copper, and has no corrosive effect on pig iron; when ammonia gas is mixed with hydrogen chloride gas, white smoke will be generated, which is ammonium chloride;