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xing2009

define the term nucleon number(mass number) of an isotope。

C.YYang

nucleon number- number of protons and neutrons present in an atom
isotope - a same element with the same number of protons but have different neutron number
nucleon number of an isotope may vary even though it is the same element because of its different number of neutrons in it, such as carbon-12 and carbon-13.

xing2009

回复 2# C.YYang


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