Atomic weight of elements

Atomic number Name Symbol Atomic weight 

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In order to predict the atomic weight of element x— newtonium —he considered the atomic mass ratios of the known noble gas elements ... 

First it is surely important to emphasise (as Brush does not) that there turned out to be independent empirical evidence for the new values assigned to these atomic weights (this re-evaluation relied, of course, on already accepted auxiliary theories—atomic weights of elements are highly theory-laden facts). It was not that chemists simply came to accept the new values because those values made those elements fit Mendeleev s table better (that would be a classic case of an ad hoc accommodation). For example, the corrected value of the atomic weight of... 

A similar activity is found in Mendeleevs first attempt at a periodic system as presented in a hand-written table. If one examines the calculations that he is carrying out one finds again an attempt to compute differences between the atomic weights of elements in the columns of his table. For example Mendeleev writes the number 27 in smaller writing below the symbols for potassium (Zn - K = 65 - 39 = 27) and again below rubidium (Cd-Rb = 112-85 = 27). 

Element X exists in nature in two isotopic forms. 60.0% of the atoms are isotope which has an atomic weight of 29.88. 40.0% of the atoms are isotope X, which has an atomic weight of 33.20. What is the weighted average atomic weight of element X ... 

The isotopic composition of the elements (including the exact atomic mass and the abundance of the isotopes), the atomic weights of elements, definitions and abbreviations are summarized in Appendix II. 

Atomic weights of elements taking oxygen as the reference... 

Isotope Chemical atomic weight of elements in nature... 

The chemical atomic weights of elements are the average relative weights (masses) of atoms of the elements, the average being for the usual isotopic composition of eUch element ... 

ATOMIC WEIGHTS OF ELEMENTS TABLE 4-2. INTERNATIONAL ATOMIC WEIGHTS. 1949... 

THE USE OF AVOGADRO S LAW IN THE DETERMINATION OF THE CORRECT ATOMIC WEIGHTS OF ELEMENTS... 

J iie imporiance ot cnstal form, and especially the phenomenon of the iso morphism of cry.stalUne substances, is evident from the use mentioned above of isomorphism in the determination the eorreeJ atomic weights of elements. 

The value of the coefficient of expansion is characteristic of the substance. It has not yet been found possible to connect this quantity with chemical properties, such as the atomic weight of elements, or the molecular weight of compounds. 

If the array is one-dimensional, only one pointer argument need be specified. Example If the reference C 2 C 102 contains the atomic weights of the elements, arranged in order of atomic niunber, then =INDEX( C 2 C 102,51) returns the atomic weight of element number 51. 

It offers a method of determining atomic weights of elements whose quivalents or combining weights are known. In this way lieryllium,... 

In order to assign to a given element its significant number, or atomic weight, it must be experimentally determined what weight of the element is involved in chemical action with an atomic weight of some element of known value. For example if the atomic weight of element is 10, and if experiment... 

Atomic mass relative to C =12. Atomic weight of elements is given on the same scale. 

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