周期表中到目前为止有106种元素,它们可分成七个周期或十八个主、副族。这些元素也可以分为金属、非金属和惰性气体三大类。但是,高中同学走上工作岗位以后,平时听到的或在科技杂志上经常看到的却是另外的分类方法。例如,分为有色金属、轻金属、重金属、贵金属、贱金属、稀有元素、稀有金属、稀土元素和放射性元素等。而这样的分类方法却不为同学们 There are 106 elements in the periodic table so far, and they can be divided into seven cycles or eighteen main and sub-family. These elements can also be divided into three major categories of metals, non-metals and inert gases. However, when high school students go to work, what they usually hear or often see in technology magazines is another classification method. For example, it is divided into non-ferrous metals, light metals, heavy metals, precious metals, base metals, rare elements, rare metals, rare earth elements, and radioactive elements. And this classification method is not for the students