Chemical symbols element names used with

The accepted standard for assigning symbols is based upon a proposal by the Swedish chemist, Baron J8ns Jakob Berzelius, in 1814. Berzelius suggested that the initial letter of the Latin name of the element be used as its chemical symbol. When names of two or more elements began with the same letter, the next distinctive letter of the name was to be added. This system was later extended for the derivation of symbols from non-Latin names assigned to elements. 

A single unstable compound of known composition is placed in the main first volume and is located on the basis of its empirical molecular formula expressed in the Hill system used by Chemical Abstracts (C and H if present, then all other element symbols alphabetically). The use of this indexing basis permits a compound to be located if its structure can be drawn, irrespective of whether a valid name is known for it. A representation of the structure of each compound is given on the third bold title line while the name of the compound appears as the first bold title line. References to the information source are given, followed by a statement of the observed hazard, with any relevant explanation. Cross-reference to similar compounds, often in a group entry, completes the entry. See Trifluoroacetyl nitrite p. 244. 

Bohrium - the atomic number is 107 and the chemical symbol is Bh. The name derives from the Danish physicist Niels Bohr, who developed the theory of the electronic structure of the atom. The first synthesis of this element is eredited to the laboratory of the GSI (Center for Heavy-Ion Research) under the leadership of the German scientists Peter Armbruster and Gunther Mhnzenberg at Darmstadt, Germany in 1981, using the reaction ° Bi ( Cr, n) Bh. The longest half-life associated with this unstable element is 17 second Bh. 

Nobelium - the atomic number is 102 and the chemical symbol is No. The name derives from Alfred Nobel , the discoverer of dynamite and founder of the Nobel prizes. It was first synthesized in 1966 by the Russian scientists from the JINR (Joint Institute for Nuclear Research) lab in Dubna, Russia under Georgi Flerov. Earlier claims to have synthesized Nobelium beginning in 1957 were shown to be erroneous but the original name was retained because of its videspread use throughout the scientific literature. The longest half-life associated with this unstable element is 58 minute o. 

Seaborgium - the atomic number is 106 and the chemical symbol is Sg. The name derives from the American chemist Glenn Theodore Seaborg , who led a team that first synthesized a number of transuranium elements. The element Seaborgium was first synthesized by American scientists from the University of California lab in Berkeley, California imder Albert Ghiorso, who used the nuclear reaction Cf ( 0,4n) Sg. The longest half-life associated with this unstable element is 21 second Sg. 

Because the elements are the building blocks of all materials in the universe, we need an easy way to identify and refer to them. For this purpose, each chemical element is identified by an internationally used symbol consisting of one or two letters. The first letter of an element s symbol is always capitalized. If the symbol has a second letter, it is a lowercase (small) letter. The symbol is an abbreviation of the element s name, but some symbols represent names in languages other than English. The 10 elements whose symbols and names have different first letters are listed in Table 1.4. A list of the names and symbols of the first 109 elements, along with some other information, is presented in a table inside the back cover of this book. In that table, the elements are alphabetized according to their names, but duplicate entries appear under the initial letter of the symbols for the elements in Table 1.4. 

Most of the symbols are clearly derived from the English name of the element, but a few come from older Latin names, such as iron (Fe, ferrum), potassium (K, kalium), and sodium (Na, natrium) It is important to know the names and symbols of the most common elements, because chemical symbols are used in all areas of science. Practicing with flashcards is the easiest way to memorize the symbols and names. 

T TABLE 1.2 lists some common elements, along with the chemical symbols used to denote them. The symbol for each element consists of one or two letters, with the first letter capitalized. These symbols are derived mostly from the English names of the elements, but sometimes they are derived fi-om a foreign name instead (last column in Table 1.2). You will need to know these symbols and learn others as we encounter them in the text. 

Berzelius who first used symbols to name elements, coined the word isomer through his work with chemical atomic weights. Not to be confused with isotopes, chemical element isomers have the same molecular formula, but different structural configurations. 

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