Heavy metals refer to those with specific gravity greater than 5Metal(Generally, it refers to the metal with density greater than 4.5g/cm3).Heavy metals refer toRelative atomic massMetals greater than 55.For example, the relative atomic mass of iron is 56, more than 55, so it is also a heavy metal.There are about 45 kinds of heavy metals, generally belonging toTransitional element。Such as copper, lead, zinc, iron, cobalt, nickel, manganese, cadmium, mercury, tungsten, molybdenum, gold, silver, etc.Although manganese, copper, zinc and other heavy metals areLife activitiesRequiredtrace elementHowever, most heavy metals such as mercury, lead and cadmium are not necessary for life activities, and all heavy metals above a certain concentration are toxic to human beings.
heavymetallic elementRefers toStandard statusThe metal elements with the density of lower elemental matter greater than 4500kg/m3 are different from light metal elements (such as aluminum and magnesium).It mainly refers to mercury, cadmium, lead, chromium andMetalloidArsenic and other toxic elements can come from the mining of mineral deposits, exposing minerals containing heavy metal elements from deep underground to the surface, or discharged into soil, atmosphere or water through industrial processing.The degree of harm of pollution is very significant, which is obvious to organismsToxic effects。[1]
In addition, different ions have different colors,Copper ionGenerally blue (thickCupric chlorideThe solution is green, which is an exception),Ferrous ionIt is generally light green,Iron ionIt is generally yellow.stayFlame reactionCopper is green and barium is yellow green.
