wt. Abbreviation: at. The average mass of a chemical element, expressed in atomic mass units. Learn more. Définition atomic weight dans le dictionnaire anglais de définitions de Reverso, synonymes, voir aussi 'atomic age',atomic bomb',atomic clock',atomic cocktail', expressions, conjugaison, exemples Definition von atomic weight im Englisch Englisch wörterbuch A term used to represent the mean relative atomic mass of an element in nature, as distinct from the relative atomic mass of a single isotope Former term for the more specific relative atomic mass. 1 atomic mass unit is defined as 1/12 of the mass of a single carbon-12 atom. atomic weight definition in English dictionary, atomic weight meaning, synonyms, see also 'atomic age',atomic bomb',atomic clock',atomic cocktail'. Atomic weight definition is - the mass of one atom of an element; specifically : the average mass of an atom of an element as it occurs in nature that is expressed in atomic mass units. It is the weighted average of the masses of natural isotopes. atomic weight definition: 1. another term for relative atomic mass specialized 2. another term for relative atomic mass…. 2. Cherchez atomic weight et beaucoup d’autres mots dans le dictionnaire de définitions en anglais de Reverso. Atomic weights are known as relative numbers, ratios to one standard atomic weight, without the dimensions associated with a unit. The atomic weight of chlorine is about 35.44 amu. This is synonymous with atomic mass. Atomic Weight is the ratio of average mass of the atoms of a chemical element to some standard. Thus, the isotope of plutonium just discussed would be written as: 94. 1922, Leicester F. Hamilton, Calculations of Analytical Chemistry, page 38: The equivalent weight of an element or compound is that weight equivalent in reactive power to one atomic weight of hydrogen. Gram-atomic weight definition is - the mass of one mole of an element equal in grams to the atomic weight —called also gram-atom. where p i is the percentage or relative abundance of an isotope i of atomic mass m i . n. The average mass of an atom of an element, usually expressed relative to the mass of carbon 12, which is assigned 12 atomic … (Glossary of terms in quantities and units in Clinical Chemistry (IUPAC-IFCC Recommendations 1996)) on page 990 . The standard atomic weight of a chemical element is the weighted arithmetic mean of the … n. The mass of an atom, usually expressed in atomic mass … Delivered to your inbox! What does atomic weight mean? Test Your Knowledge - and learn some interesting things along the way. Meaning of atomic weight. Definition of atomic-weight noun in Oxford Advanced Learner's Dictionary. The atomic weight is the average mass of the atoms of an element, calculated using the relative abundance of isotopes in a natural element. “Atomic weight.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/atomic%20weight. Standard Atomic Weight - This is the expected atomic weight or relative atomic mass of an element sample in the Earth's crust and atmosphere. Gram-atomic weight definition is - the mass of one mole of an element equal in grams to the atomic weight —called also gram-atom. See more. Industry Dictionaries. An atomic mass unit is defined as 1/12th the mass of a carbon-12 atom. Chemistry glossary Definition of atomic weight and examples. Pu 239 or as. Its concept is fundamental as most of the chemical reactions occur according to the simple numeric relationships between the atoms. A carbon-12 atom is assigned 12 atomic mass units. It can also be defined as the weight of a distinct unit of an element or the amount of matter of the sole weight of an isotope (a variant of a … atomic weight (Noun) A term used to represent the mean relative atomic mass of an element in nature, as distinct from the relative atomic mass of a single isotope. Meaning of atomic weight. Sources: Green Book, 2 nd ed., p. 41 PAC, 1996, 68, 957. Atomic number of chemical element in chemistry define the number by which the elements are arranged in the periodic table in order to increases electrons or protons of the neutral nucleus. Learn more. Atomic Weight. atomic weight definition: 1. another term for relative atomic mass specialized 2. another term for relative atomic mass…. After this point, the standard was changed to be 1/12th the weight of a carbon-12 atom in its ground state. Atomic-weight values originally were considered to be constants of nature and, as such, did not have any associated uncertainties. Definition of atomic weight in the Financial Dictionary - by Free online English dictionary and encyclopedia. Basis for the atomic weight unit Before 1961, a unit of atomic weight was based on 1/16 (0.0625) of the weight of an oxygen atom. atomic weight - WordReference English dictionary, questions, discussion and forums. Standard Atomic Weights. Definition of atomic weight in the AudioEnglish.org Dictionary. Atomic weight of Hydrogen is 1.0079 when rounded to the nearest tenth = 1.0 gram. Atomic-weight values originally were considered to be constants of nature and, as such, did not have any associated uncertainties. 1. Define atomic mass. (chemistry) the ratio of the atomic mass of an element to half the atomic mass of carbon-12. Learn more. Meaning, pronunciation, picture, example sentences, grammar, usage notes, synonyms and more. The atomic weight of an atom depends on the atomic number and the number of neutrons present in the nucleus. Send us feedback. The unit is dimensionless. Definition of Atomic Mass Atomic mass is defined as the number of protons and neutrons contained in an individual unit of a substance. The modern periodic system is formed on the basis of atomic number and electronic configuration of the atom but Mendeleev classification is based on atomic weight or mass. Atomic weights (M) of atoms are related to the sum of the number of protons and neutrons.But this number physically corresponds to the actual weight of an atom. In other words, a relative atomic mass tells you the number of times an average atom of an element from a given sample is heavier than one-twelfth of an atom of carbon-12. So, for these elements, the total nucleon count (sum of the number of protons and neutrons in the atomic nucleus) is usually cited in the place of the standard atomic weight. Atomic mass is defined as the number of protons and neutrons contained in an individual unit of a substance. 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