Metals and metalloids（termed as metals in this article）are important constituent elements of the earth＇s crust.A number of metals,if present in excess,are toxic to organisms and therefore they are usually defined a...Metals and metalloids（termed as metals in this article）are important constituent elements of the earth＇s crust.A number of metals,if present in excess,are toxic to organisms and therefore they are usually defined as toxic metals.展开更多
文摘Metals and metalloids（termed as metals in this article）are important constituent elements of the earth＇s crust.A number of metals,if present in excess,are toxic to organisms and therefore they are usually defined as toxic metals.
