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mass numbers are whole numbers because the mass number is number of protons in an atom, plus the number of neutrons. you can only have a whole neutron and or proton, therefore, all mass numbers are whole numbers.

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Q: Why are mass numbers whole numbers?
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Are the mass numbers but not the atonic mass whole numbers?

correct


Why the mass numbers on the periodic table of elements are rarely whole numbers?

Elements also possess isotopes. So their average atomic mass is rarely whole number.


Why is the mass numbers of isotopes exact whole numbers but the relative masses of most Atoms are not exact whole numbers?

Relative atomic massisthe ratio of the averagemassofatomsof anelementto 1/12 of the mass of an atom ofcarbon-12. The mass number of an isotope is the sum of protons and neutrons in the atoms of the isotope.


Why is the relative atomic mass of chloride not a whole number?

Because relitive atomic masses are NEVER whole numbers.


Does the mass number of an element have to be a whole number?

Approximately, yes. But the mass number is an average of the masses of the isotopes of the element, weighted together according to their abundance. This averaging of different whole numbers results in the mass number not being a whole number.


The atomic mass of the elements are not whole value numbers because of the existence of?

D. Protons


How do isotopes differ and why is the atomic number of elements not a whole number?

Isotopes of an element have the same number of protons but different numbers of neutrons, resulting in different atomic masses. The atomic number of elements is not a whole number because it represents the number of protons in the nucleus, which can be a whole number, but the atomic mass accounts for the presence of isotopes with different numbers of neutrons, leading to fractional values.


Why is the atomic mass of nobelium a whole number?

The atomic mass of nobelium reported as a whole number is usually the average atomic mass of its isotopes, taking into account the natural abundance of each isotope. Since this average is calculated from the weighted average of the isotopes' masses, the result often appears as a whole number.


What is the mass of mercury Hg?

The atomic mass of mercury (Hg) is approximately 200.59 grams per mole.


Why do you round mass numbers to the nearest whole number?

That is done mainly for basic chemistry. The normal practice is to take the weighted average of the various isotopes which, in almost all cases leads to numbers which are not whole.


Why is lithium's mass number a decimal number?

The mass number is a whole number, but the atomic mass may not be. Mass numbers are the total number of neutrons and protons in an isotope (different from atomic numbers, which are the whole numbers of protons only). These are also whole numbers, and for most lithium, it is 7. The mass number is 6 for lithium-6, which has only 3 neutrons. However, the "atomic mass" of an element is measured in atomic mass units, which are 1/12 of the weight of a carbon-12 atom (6 protons and 6 neutrons). Since neutrons are slightly heavier than protons, and there are more neutrons than protons in lithium-7 (3 protons to 4 neutrons), the atomic mass is slightly more than 7.


What are two ways in which whole numbers and decimal numbers are different?

Whole numbers are a proper subset of decimal numbers. All whole numbers are decimal numbers but not all decimal numbers are whole numbers.