Isotope, common elements, table

TABLE B.2 Element Some Isotopes of Common Elements Atomic number, Symbol Z Mass number, A Abundance, %... 

Carbon, a common element in the outer crust of the earth, and the main component of all biological and organic substances, occurs in three isotopic forms carbon-12 or C-12 for short (whose chemical symbol is 12C), carbon-13 or C-13 (13C), and carbon-14 or C-14 (14C) (see Fig. 8 and Table 66). 

Interactions between one or more nuclei and the unpaired electron yield a wealth of information concerning molecular structure. In addition, they have proven invaluable in the identification of paramagnetic species. As indicated in Table II many of the common elements have isotopes with nuclear magnetic spins which distinguish them from the other elements. If the isotopes of interest are not sufficiently abundant in the natural form, enriched samples may be purchased. The quantity used in surface studies is usually quite small, so relatively expensive isotopes such as 170 can be studied. In fact, it is possible to recover most of the isotope following an experiment, should the cost require it. 

Table 2.5 Natural isotopic abundances and monoisotopic masses of common elements...

Table 9.10 Principle stable isotopes and relative abundances of some common elements...

Isotopic abundances are listed either as their sum being 100 % or with the abundance of the most abundant isotope normalized to 100 %. The latter is used throughout this book because this is consistent with the custom of reporting mass spectra normalized to the base peak (Chap. 1). The isotopic classifications and isotopic compositions of some common elements are listed below (Table 3.1). A full table of the elements is included in the Appendix. 

Table 3.1. Isotopic classifications and isotopic compositions of some common elements lUPAC 2001 [4,5]...

Table 1.1 Isotopic abundance of common elements. Interesting to note is that chlorine and bromine have t /o naturally intense isotopes.

Table 2.1 Relative Isotope Abundances of Common Elements ...

Table 2.1 lists the principal stable isotopes of the common elements and their relative abundance calculated on the basis of 100 molecules containing the most common isotope. Note that this presentation differs from many isotope abundance tables, in which the sum of all the isotopes of an element adds up to 100%. 

Table 16.1—Atomic mass of the isotopes of elements commonly encountered in organic compounds.

A radioactive element is an element that disintegrates spontaneously with the emission of various rays and particles. Most commonly, the term denotes radioactive elements such as radium, radon (emanation), thorium, promethium, uranium, which occupy a definite place in the periodic table because of their atomic number. The term radioactive element is also applied to the various other nuclear species, (which arc produced by the disintegration of radium, uranium, etc.) including (he members of the uranium, actinium, thorium, and neptunium families of radioactive elements, which differ markedly in their stability, and are isotopes of elements from thallium (atomic number 81) to uranium (atomic number... 

Table A4.1 Atomic weights of isotopes of some common elements 1436...

Table 15.3 Natural Abundances of Isotopes of Some Common Elements...

Whether or not a high-resolution mass spectrometer is available, molecular ion peaks often provide information about the molecular formula. Most elements do not consist of a single isotope, but contain heavier isotopes in varying amounts. These heavier isotopes give rise to small peaks at higher mass numbers than the major M+ molecular ion peak. A peak that is one mass unit heavier than the M+ peak is called the M+l peak two units heavier, the M+2 peak and so on. Table 12-4 gives the isotopic compositions of some common elements, showing how they contribute to M+l and M+2 peaks. 

Table 1 Nuclear spin data of common elements and isotopes ...

Table 2 Common Elements with Their Naturally Occurring Isotopic...

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