atomic weight


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Related to atomic weight: molecular weight

atomic weight

n.
The average mass of an atom of an element, usually expressed relative to the mass of carbon 12, which is assigned 12 atomic mass units.

atomic weight

n
(Chemistry) the former name for relative atomic massAbbreviation: at wt

atom′ic weight′


n.
the average weight of an atom of an element, based on 1/12 the weight of the carbon-12 atom. Abbr.: at. wt.

atomic weight

The average mass of a chemical element, expressed in atomic mass units. The atomic weight of an element having more than one principal isotope is calculated both from the atomic masses of the isotopes and from the relative abundance of each isotope in nature. For example, the atomic weight of the element chlorine is 35.453, determined by averaging the atomic masses and relative abundances of its two main naturally occurring isotopes, which have atomic masses of about 35 and 37. Compare atomic mass.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.atomic weight - (chemistry) the mass of an atom of a chemical element expressed in atomic mass unitsatomic weight - (chemistry) the mass of an atom of a chemical element expressed in atomic mass units
mass - the property of a body that causes it to have weight in a gravitational field
combining weight, eq, equivalent weight, equivalent - the atomic weight of an element that has the same combining capacity as a given weight of another element; the standard is 8 for oxygen
meq, milliequivalent - one-thousandth of an equivalent
chemical science, chemistry - the science of matter; the branch of the natural sciences dealing with the composition of substances and their properties and reactions
Translations
References in periodicals archive ?
This was upsetting news, since oxygen atoms had been used for a century as the standard against which atomic weights could be determined.
In 1913 Richards found definite variations in the atomic weight of lead, and this strongly supported the isotope concept.
Mendeleyev had arranged the elements in order of increasing atomic weight but had to place some slightly out of order to keep them in their proper families.
Rayleigh went on to measure the atomic weight of nitrogen and then encountered a puzzle.
Helium, however, with the lowest atomic weight of the inert gases, remained a gas even at liquid-hydrogen temperatures.
Another student from one of the high schools in Thimphu, Yangchen Dolkar, who also signed the petition, said the atomic weight table should have been provided as it had been in the past exams.
Rare earth elements can be divided into the light one, the medium one and the heavy one by their atomic weight, physical and chemical properties.
One of the most interesting parts of the book, and my favourite, is the explanation of the atomic composition of gold, and why such an atomic weight is a rare formation.
In 1869 Russian chemistry professor Dmitri Mendeleev published his Periodic Table, listing 63 elements in rows or columns in order of atomic weight.
These simple analytic equations, which obviously depend on parameters such as accelerating voltage, specimen thickness, density, atomic weight and number, can easily be implemented in the software of any x-ray microanalysis system.
The word of God, though, enjoyed its own atomic weight.
My heart never was my own; I won it guessing the atomic weight of