这里主要取决于 the mass of这个词组里的the，虽然意思为“大量的”，但它后面的名词接的是单数形式，但如果是a mass of其后就接的是复数名词了！
Atomicnumber(Z)=numberofprotonMassnumber(A)=numberofproton+numberofneutron Foranunchargedatom: No.ofproton=atomicnumberNo.ofneutron=massnumber-no.ofproton(atomicnumber)No.ofelectron=no.ofproton=atomicnumber Isotope–atomsofthesameelementwithdifferentmasses Useofsymbols Massno.Atomic...
1 atom 12 C“weighs” 12 amu On this scale 1 H = 1.008 amu 16 O = 16.00 amu Atomic mass is the mass of an atom in atomic mass units (amu) Micro World atoms & molecules Laboratory scale measurements No matter what its source, a particular ...
atomic mass- (chemistry) the mass of an atom of a chemical element expressed in atomic mass units atomic weight,relative atomic mass 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 ...
Both atomic mass and atomic weight relyon the atomic mass unit(amu), which is 1/12th the mass of an atom of carbon-12 in its ground state. Can Atomic Mass and Atomic Weight Ever Be the Same? If you find an element that exists as only one isotope, then the atomic mass and the...
atomic mass (u) ≈ number of protons + number of neutrons Or A=Z+NA=Z+N where: AA— Mass number (total number of protons and neutrons); ZZ— Number of protons in the atom; and NN— Number of neutrons in the atom. Note that the mass of an atom will be slightly less than its ...
The difference between the nominal mass and the monoisotopic mass of an atom, molecule, or ion, positive or negative value, is the mass defect. The value of accurate mass measurement is illustrated in the following examples: (1) to distinguish compounds with the same integer nominal (molecular...
This is defined as “the average mass of the molecule divided by 1/12 of the mass of an atom of the nucleide C12.” The older term molecular weight is still widely used by polymer technologists. Frequently, quoted molecular weights are dimensionless, but again can be quoted in kg mol−...
The mass of any atom in grams can thus be found by dividing the gram-atomic mass of the isotope by Avogadro's number. For example, the mass of an atom of carbon-12 is its gram-atomic mass (12 grams) divided by Avogadro's number (NA): mass of12C=12 gm6.023×1023=1.99×10-...