M
Mass Number
AllChemicals — The Online Chemical Glossary | https://allchemicals.info/chemical/571-mass-number
What is Mass Number?
The mass number (A) of a nuclide is the total number of protons and neutrons (nucleons) in its nucleus. It is used together with the atomic number (Z) to specify a particular isotope: ᴬZX. For example, carbon-12 (¹²₆C) has mass number 12 (6 protons + 6 neutrons). The mass number is approximately equal to the atomic mass in atomic mass units.
Key Facts
Term
Mass Number
Index
All "M" terms
Frequently Asked Questions
The mass number (A) of a nuclide is the total number of protons and neutrons (nucleons) in its nucleus. It is used together with the atomic number (Z) to specify a particular isotope: ᴬZX. For example, carbon-12 (¹²₆C) has mass number 12 (6 protons + 6 neutrons). The mass number is approximately equal to the atomic mass in atomic mass units.
More "M" Terms
2-Methyltetrahydrofuran
C5H10O
m-Chloroperoxybenzoic acid
C7H5ClO3
Macromolecule
Magnesium
Mg
Magnesium carbonate
MgCO3
Magnesium chloride
MgCl2
Magnesium hydroxide
Mg(OH)2
Magnesium oxide
MgO
Magnesium sulfate
MgO4S
Magnetic Quantum Number
m_l quantum number: −l to +l integers; e.g., p: m_l = −1, 0, +1
Main Group Elements
Malachite green
C23H25ClN2
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