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mass number
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noun Physics.
the integer nearest in value to the atomic weight of an atom and equal to the number of nucleons in the nucleus of the atom. Symbol: A
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THINGAMABOB OR THINGUMMY: CAN YOU DISTINGUISH BETWEEN THE US AND UK TERMS IN THIS QUIZ?
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In the UK, COTTON CANDY is more commonly known as…
Origin of mass number
First recorded in 1920–25
Words nearby mass number
mass meeting, mass merchandiser, mass movement, mass murder, mass noun, mass number, mass observation, Masson disk, Massorete, massotherapy, mass-produce
Dictionary.com Unabridged
Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
How to use mass number in a sentence
People were going out to vote in mass numbers to vote Barack in office.
Now, people are voting in mass numbers to vote the current president out of office.
There, you can donate to the cause and join the “mass number of Manson supporters worldwide.”
In the black peaty mass Number 5, fragments of wood of the oak, yew, and fir have been recognised.
The Geological Evidence of The Antiquity of Man|Charles Lyell
British Dictionary definitions for mass number
mass number
noun
the total number of neutrons and protons in the nucleus of a particular atomSymbol: A Also called: nucleon number
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Scientific definitions for mass number
mass number
The total number of protons and neutrons in the nucleus of an atom. For example, nitrogen has 7 protons and 7 neutrons in its nucleus, giving it a mass number of 14. Isotopes of elements are distinguished by their mass number; for example, carbon-12 and carbon-14 have mass numbers of 12 and 14 respectively. Also called nucleon number Compare atomic mass atomic weight.
The American Heritage® Science Dictionary
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