Cobalt atomic symbol

In some cases, it would be convenient to condense the electron configuration. In this condensed form, the electronic configuration of the previous noble gas forms a core represented by the atomic symbol of the element enclosed in brackets (i.e., [He] or [Ne]). The electrons added since the noble gas, follow the noble gas core. For example, cobalt can be represented as an argon core plus the 4s and 3d electrons. Thus, ls22s22p63s23p64s23d7 becomes [Ar]4s23d7. 

Each element is represented by a unique one- or two-letter symbol. For example, the symbol for hydrogen is H, oxygen s symbol is O, and nitrogen s symbol is N. When two or more elements have names that begin with the same English letter, all but one of the elemental symbols has a second letter. The second letter is always lower case. For example, carbon is C, chlorine is Cl, cobalt is Co, and chromium is Cr. Chemists understand that the symbol for an element represents more than one or two letters. Instead, a chemist sees the symbol Ni and immediately thinks of nickel atoms. 

Cobalt - the atomic number is 27 and the chemical symbol is Co. The name derives from the German kobold for evil spirits or goblins , who were superstitiously thought to cause trouble for miners, since the mineral contained arsenic which injured their health and the metallic ores did not yield metals when treated with the normal methods. The name could also be derived from the Greek kobalos for mine . Cobalt was discovered in 1735 by the Swedish chemist Georg Brandt. 

The atomic number, which appears above each element symbol, represents the meaningful order in the periodic table. When an element is referred to by an integer, this number means the atomic number, not the atomic weight. Thus, element 27 is cobalt (whose atomic number is 27), not aluminum (whose atomic weight is 27). In Chapters 2 and 3, these two concepts are more carefully defined for now, simply bear in mind the distinction between atomic number and atomic weight. 

Symbol Ni atomic number 28 atomic weight 58.693 a transition metal element in the first triad of Group VIll(Group 10) after iron and cobalt electron configuration [Ar]3d 4s2 valence states 0, -i-l, +2, and -f-3 most common oxidation state +2 the standard electrode potential, NF+ -1- 2e Ni -0.237 V atomic radius 1.24A ionic radius (NF+) 0.70A five natural isotopes Ni-58 (68.08%), Ni-60 (26.22%), Ni-61 (1.14%), Ni-62 (3.63%), Ni-64 (0.93%) nineteen radioactive isotopes are known in the mass range 51-57, 59, 63, 65-74 the longest-lived radioisotope Ni-59 has a half-life 7.6x10 years. 

One of the most elegant approaches to the problem to date involves a cofacial cobalt-porphyrin system adsorbed on to graphite electrodes. The active porphyrin is represented in (35). The mechanistic scheme which has been proposed is represented schematically in equation (46), where the symbol CoIU CoUI represents one bifacial porphyrin entity in which both metal atoms are... 

Chemists write symbols together in formulas to identify compounds. For example, the letters CO represent a compound of carbon and oxygen. Be careful to distinguish the formula CO from the symbol Co, which represents the element cobalt. The capitalization of letters is very important Formulas are sometimes written with subscripts to tell the relative proportions of the elements present. For example, H2O represents water, which has two atoms of hydrogen for every atom of oxygen present. More about formulas will be presented in Section 5.1. 

The symbol for an isotope stands for the nucleus of that isotope. Recall that the mass number of an isotope is written as a left superscript on the symbol of the element and that the atomic number may appear as a left subscript. For example, cobalt-60 may be represented as either Co or 27C0. The symbol of... 

Arsenic is a metallic element (symbol As atomic no. 33), which exists in several allotropic forms. Various ores contain crystalline forms of arsenic salts cobaltite contains cobalt arsenic sulfide mispickel (arsenopyrite) iron arsenic sulfide orpiment arsenic trisulfide proustite (ruby silver ore) silver arsenic sulfide realgar arsenic sulfide and tennantite copper arsenic sulfide. 

Cobalt is a metallic element (symbol Co atomic no. 27). It is an important constitnent of the cobalamins (vitamin B12) and is fonnd as arsenates and arsenides in natnrally occnrring minerals snch as erythrite, skntterndite, and smaltite. 

Any element in the periodic table can undergo beta decay. A beta particle is an electron, commonly symbolized as IE" or e". An example of beta decay is the conversion of cobalt 60 into nickel 60 by the following reaction Co IE Ni + e. The atomic number of the daughter isotope is one greater than that of the parent isotope, which maintains charge balance. The mass number, however, does not change. 

We now navigate to molecule-add and choose molecule-add-atom to create the cobalt(III) center. In the symbol subtab, we set the atom type to C03 and press confirm. The atom appears in the molecule view. The first nitrogen atoms are now added by changing the atom type and position to NT and (1.95,0,0), respectively. For the second nitrogen atom, we choose (0, 1.95, 0), and so on. 

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