What is the isotopic composition of an element?
The identity of an element is determined by the number of PROTONS it contains in its nucleus. Nuclei of the same element may, however contain different number of NEUTRONS.
You know that the atomic nucleus contains a certain number of PROTONS, massive positively charged particles, and NEUTRONS, massive NEUTRALLY charged particles.
The number of positively charged particles gives the identity of the nucleus; this is
Take carbon as an exemplar. Most carbon nuclei (and ALL contain 6 PROTONS in their nuclei, WHY?) have 6 neutrons in their nuclei as well. A mole (a large number) of
As atoms get bigger, they can support different numbers of isotopes. Actinides and lanthanides have a lot of different isotopes, some of which may be used in nuclear reactions.
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