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The mass of an atom is determined by the number of protons and neutrons, which each have a mass, by definition, of 1 AMU. The mass of the electrons in the surrounding cloud doesn't add enough to change the value within a reasonable number of decimal places.
Since the nuclear particles have a mas value of 1.0000..., the mass of a single atom has no decimal places. The decimal place values on the Periodic Table come from the percentages of isotopes occurring naturally changing the collective mass of the element. This gets important when we work with elements in gram amounts. In general, atomic weights (or atomic masses) of given elements that you see on the periodic table are actually weighted averages across the naturally occurring isotopes of that element.
So if you look up on WebElements.com what the isotopic abundances of neon are, you will find that there is 90.48% of neon-20, 0.27% of neon-21, and 9.25% neon-22. The atomic weight of 20.18 grams per mole comes from (0.9048 x 20) + (0.0027 x 21) + (0.0925 * 22).
So a large sample of neon will act as though its mass were 20.18 grams per mole, but any individual atom of neon will have a mass close to 20, 21 or 22 grams per mole.
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What is the mass of a single atom of helium?
The atomic mass of Helium is 4.002602. The atomic mass is the combined number of protons and neutrons in the atom.
Is atomic mass and atomic diameter the same thing?
No, the atomic mass is the average mass of the atom and the atomic diameter is the average diameter of the atom
What does atomic mass represent of an element represent?
Atomic Mass represents the mass of atom. We use mass of protons and neutrons.
Atomic mass of an atom is called?
What do you mean? Atomic mass of an atom is the weighted average mass of all the naturally occurring isotopes of that element, measured in amu (=atomic mass unit). I do not know how do you want to call it, it is just atomic mass, average atomic mass, mass of an atom, atom's mass...
How many electrons belong to a neutral atom with an atomic mass of 36 amu?
A neutral atom with an atomic mass of 36 amu will have 36 electrons. This is because the atomic mass of an atom is determined by the sum of its protons and neutrons, and in a neutral atom, the number of electrons is equal to the number of protons.
What is the earths atomic mass?
Since the Earth is not a single atom, nor a collection of similar atoms, it does not have an atomic mass. Atomic mass is a measure of how much matter is contained by a specific atom.
What does the number above the symbol represent?
The atomic number.
What is the mass of a single atom of helium?
The atomic mass of Helium is 4.002602. The atomic mass is the combined number of protons and neutrons in the atom.
What is the Word for mass of protons and neutrons in a single atom?
atomic weight
How do you determine the atom the atomic mass of an atom?
Proton + Nuetron = Atomic Mass
What is the atomic mass of an atom?
The atomic mass of an atom is the combined mass of the protons and neutrons in the nucleus.
Is atomic mass and atomic diameter the same thing?
No, the atomic mass is the average mass of the atom and the atomic diameter is the average diameter of the atom
What is the atomic number for Ag?
Since a single atom is specified, the mass number of the particular isotope that the atom represents needs to be known. The quotient of the mass number and Avogadro's Number will give the approximate mass of the single atom in grams. (For the most accurate answer, the slight difference in mass between a proton and a neutron and the mass of the electrons in the atom will also need to be considered.)
What is the number of neutrons in an atom affects the atomic what?
The number of neutrons in an atom can affect the atomic mass of an atom.
What does atomic mass represent of an element represent?
Atomic Mass represents the mass of atom. We use mass of protons and neutrons.
The atomic mass of an atom is the?
The atomic mass of an atom is the mass of 6.011 X 10^23 atoms of that element.
Atomic mass of an atom is called?
What do you mean? Atomic mass of an atom is the weighted average mass of all the naturally occurring isotopes of that element, measured in amu (=atomic mass unit). I do not know how do you want to call it, it is just atomic mass, average atomic mass, mass of an atom, atom's mass...
