atomic mass

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1. a lump or collection of cohering particles.
2. that characteristic of matter that gives it inertia. Symbol m.
atomic mass atomic weight; see also atomic mass unit.
inner cell mass an internal cluster of cells at the embryonic pole of the blastocyst which develops into the body of the embryo.
lean body mass that part of the body including all its components except neutral storage lipid; in essence, the fat-free mass of the body.
relative molecular mass technically preferable term for molecular weight.

atomic mass (A)

the average mass, relative to an atom of carbon, of an atom of an element based on the natural isotopic mix of that element. Also called atomic weight. See also atomic mass unit.

a·tom·ic mass

(ă-tomik mas)
Total number of protons, neutrons, and electrons in an atom.
References in periodicals archive ?
To determine important characteristics of the atomic number some variants of graphical functions of the atomic mass versus the nucleus of all the elements were studied, including No.
Students are asked to observe their WEEKLY LAB notes and to consider whether an atom's number of protons affects the size of its atomic mass.
Step 5: The relationships between molar mass and relative atomic mass, and between mole and atomic mass unit were explained.
92) because of the loss of two protons, and the atomic mass decreases by four (234 from 238) because of the loss of two protons and two neutrons.
We must conclude that mass, represented here by the additional atomic mass of neutrons, does not affect backscattering of electrons under microprobe conditions.
Each Element has two Atomic Numbers and same Atomic Mass which accounts for all behaviors of Elements and proof of Parallel Universes.
The main sign according to which the elements of the long Periods are split into two rows is their oxidation order: the same numerical values of it are repeated in the same Period with increase of atomic mass of the elements.
Up to now, the atomic mass was listed as an average value (1.
The constant refers to the number of atoms in a sample whose bulk mass in grams equals the relative atomic mass of the element.
While avoiding overlap with other papers in this volume, this article summarizes results from: 1) early work on crystallization as a method of purification, in contributions to sugar chemistry, and in solution growth of large crystals; 2) the NBS/ARPA Program of research on crystal growth and characterization; 3) the NBS Free-Radical Research Program; 4) the XRCD method as a direct path to relative atomic mass data and the fundamental physical constants; 5) the dynamical theory of x-ray diffraction; and 6) symmetry considerations such as are involved in the influence on crystals of mechanical stress or fields, and of point defect motion.
The innovative approach extends the applications of multi-parameter flow cytometry by taking advantage of the analytical power of atomic mass spectrometry to measure up to 100 biomarkers simultaneously in single cells at a rate of 1,000 cells per second.