Atomic mass table

Wapstra, A.H. and Audi, G., The 1983 Atomic Mass Evaluation. I. Atomic Mass Table, Nucl. Phys. A432 (1985) 1-54. 

A direct comparison of atomic masses (Table 19.1) lets us determine whether beta emission can take place. 

In 1829, the German chemist J.W. Dobereiner classified some elements into groups of three, which he called triads. The elements in a triad had similar chemical properties, and their physical properties varied in an orderly way according to their atomic masses. Table 3.1 shows the atomic mass, density, boiling point, and melting point for each of three elements in the halogen triad—chlorine, bromine, and iodine. Figure 3.1 shows these three elements at room temperature. 

Fig. 1.3 Dalton s first Atomic Mass Table and first models in 1808 [14]...

Modern atomic mass tables must recognize this fact because one of the properties that distinguishes these different kinds of atoms for a given element is the atomic mass. An element can exist in several isotopic forms, and all atoms of the same isotope are identical. 

Audi, G. Wapstra, A.H. The 1993 atomie mass evaluation (i) atomic mass table. Nucl. Phys. A. 1993, 565, 1-65. 

As for any physical quantity (Section 1.1), measurement of mJz values of ions is ultimately a comparison of the unknown with a standard of some kind. In the case of a mass spectrometer, the raw data transferred to the computer do not involve tnlz values at all but are specifications of the times at which electrical signals (arising from arrival of ions at the detector) are transferred to the computer during a scan of the electric and/or magnetic fields that the particular analyzer employs to separate the ions. (In the case of time of flight analyzers the relevant quantity is the time elapsed since the ions were pulsed into the flight mhe, see Section 6.4.7.) To transform these times of detection into mlz values, it is necessary to obtain a cahhration of time vs mlz obtained using mass cahbration standards that yield ions of known mlz calculated from their molecular formulae and values of atomic masses (Table 1.4). It can be mentioned that... 

Table B-1 SI Measurement Table B-2 Unit Symbols Table B-3 Symbols Table B-4 Physical Constants Table B-5 Enthalpy of Combustion Table B-6 The Elements Symbols, Atomic Numbers, and Atomic Masses Table B-7 Common Ions Table B-8 Water-Vapor Pressure Table B-9 Densities of Gases at STP Table B-10 Density of Water Table B-11 Solubilities of Gases in Water Table B-12 Solubility Chart Table B-13 Solubility of Compounds Table B-14 Enthalpy of Formation Table B-15 Properties of Common Elements...

These results indicate that the percent isotopic abimdance of Br varies between 50.516% and 50.817%. Because of this variation, the atomic mass of bromine is best expressed as an atomic mass interval. When a representative value of the atomic mass of Br is required, we wordd use the conventional atomic mass (Table 2.2)... 

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