Transition Metals More so than any of the other major groups of elements in the periodic table, the transition metals have shaped human history and have been the workhorses of industry. The discovery of metallic copper ended the Stone...
Matter(物质)分为Pure Substance (纯净物)与Mixture (混合物): Pure Substance(纯净物)有固定的化学式,只有一种组成成分的物质,分为由单种Element(元素)组成的单质和由多种Element(元素)化合成的化合物。 Mixture(混合物)是由多种成分(也即多种Pure Substance纯净物)组成的物质,也因此没有固定的化学式。混合物...
www.periodicvideos.com铝(Aluminium)是一种金属元素,元素符号为Al,原子序数为13。其单质是一种银白色轻金属。有延展性。商品常制成棒状、片状、箔状、粉状、带状和丝状。在潮湿空气中能形成一层防止金属腐蚀的氧化膜。铝粉在空气中加热能猛烈燃烧,并发出眩目的白色火
1.TheBeginningsofthePeriodicTable•Beforewrittenhistory,peoplewereawareof someoftheelementsintheperiodictable.Elementssuchasgold(Au),silver(Ag),copper(Cu),lead(Pb),tin(Sn),andmercury(Hg).•Itwasn'tuntil1649,however,untilthefirstelementwasdiscoveredthroughscientificinquirybyHennigBrand.Thatelementwas...
They are very reactive metals, and they are never found in the element state in nature. However, their compounds are widespread. All the members of the alkali metal family form ions having a charge of 1+ only. In contrast, the elements of group IB-copper, silver, and gold-are ...
Periodic Table 元素周期表(相对分子量) PERIOD 1 IA 18 VIIIA 1 1.008 2 4 1 H Group IUPAC Group CAS Metal Semi Metal Non Metal He Alkaline Metal Chalcogens Element Hydrogen 2 IIA 1 IA Alkaline Earth Metal Halogens Element 13 IIIA 14 IVA 15 VA 16 VIA 17 VIIA Helium 3 6.94 4 9.01 Ato...
Periodic table - Elements, Groups, Families: Mendeleev’s periodic table of 1869 contained 17 columns, with two nearly complete periods (sequences) of elements, from potassium to bromine and rubidium to iodine, preceded by two partial periods of seven el
1. The Elements and The Periodic Table元素和周期表The number of protons in the nucleus of an atom is referred to as the atomic
29 Cu 铜同 copper ['kɔpə] 30 Zn 锌辛 Zinc [ziŋk] 31 Ga 镓家 Gallium ['gæliəm] 32 Ge 锗者 Germanium [dʒə:'meiniəm] 33 As 砷申 Arsenic ['ɑ:sənik] 34 Se 硒西 Selenium [si'li:niəm,-njəm] ...
Periodic table, in chemistry, the organized array of all the chemical elements in order of increasing atomic number. When the elements are thus arranged, there is a recurring pattern called the ‘periodic law’ in their properties, in which elements in t