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一、镉的性质和用途镉与锌的性质很相似,并且常在天然化合物中与锌伴生。由於镉较锌易於挥发,故当锌矿石还原时,镉首先挥发,而藉此与锌分离开来。纯镉是一种白色金属,比重为8.6,熔点为321°。在电位次序表中,镉位於锌的下面,但在氢的上面,帮能从酸中排出氢来。在电气工业中用金属镉,制造受到滑动接触磨擦的导电体。加镉能改善铜的机械性能,增进导体的寿命,同时并不减低铜的导电能力。镉是很多易熔合金的组成成份。近来镉被广泛地用,以被覆钢铁(镀镉)。
First, the nature and use of cadmium Cadmium and zinc are very similar in nature, and often associated with zinc in natural compounds. Since cadmium is more volatile than zinc, when the zinc ore is reduced, cadmium first volatilizes, thereby separating it from zinc. Pure cadmium is a white metal with a specific gravity of 8.6 and a melting point of 321 °. In the Potential Order table, cadmium is located below the zinc, but above the hydrogen, it helps to remove hydrogen from the acid. Metal cadmium is used in the electrical industry to make conductors subject to sliding contact friction. Cadmium can improve the mechanical properties of copper and improve the life of the conductor, while not reducing the conductivity of copper. Cadmium is a component of many fusible alloys. Recently, cadmium has been widely used to cover steel (cadmium plating).