Thevalenceof the elements (that is, the number of bonds formed with a standard element) is closelycorrelatedwith position in the periodic table, the elements in the main groups having maximum positive valence, or oxidation number, equal to the group number and maximum negative valence equal to ...
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...
Periodic Table of Elements PeriodicTableofElements ---元素周期表 •In1869,theRussianchemicalMendeleevelementsaccordingtorelativeatomicmassfromthesequence,andthechemicallysimilarelementsinalongitudinal,producedthefirstperiodictableoftheelements,revealsthechemistrybetweentheinnerlinks,sothatitconstitutesacompletesystem,bec...
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 number, or proton number, Z. The numbers of electrons in an electrically neutral atom is also equal to the atomic number, Z. The total mass of an atom ...
1 Alkali and Alkalinse earth metals 2 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 disc...
Periodic table of elements with information on chemical elements like gold, silver, iron, neon, helium, chlorine, copper, cobalt, and more
Periodic table of elements is a simple app that you can look up elements common properties. it is simple to use, contains a lot of information about elements and their behavior. it is interactive. you can click at any elements to see its property. on th
With Game Center integration, you can show everyone how well you know the periodic table and do your best to be the first in the ranking! Features ★ Two game modes: - Element symbol to name or - Element name to symbol ★ Two difficulty levels for each game mode ...
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...
The periodic table of the chemical elements is a tabular display of the known chemical elements. The elements are arranged by electron structure so that many chemical properties vary regularly across the table. Each element is listed by its atomic number and chemical symbol. The standard table ...