How is the atomic number of an element determined?

1 Answer
Aug 19, 2017


By the number of protons found in one atom of an element.


The atomic number tells us the number of proton atoms in a single atom of an element. It is unique to each element.

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Do not be confused with isotopes, where an has the same number of protons (as its other isotopes), but a different number of neutrons.


In this example, Hydrogen's atomic number remains the same - at 1. The only difference are the number of neutrons.

Hope this helps :)