How do protons identify an atom?

1 Answer
Jan 1, 2018

The number of protons gives #Z_"atomic number"#......the which unequivocally identifies the given atom.....


#Z# is the so-called #"atomic number"#, the which gives the identity of the of the element. #Z=1#, the element is hydrogen; #Z=2#, the element is helium; .... #Z=46#, the element is palladium.... From where do I get these numbers. Each of these elements has a distinct and characteristic chemistry.

In the neutral atom, the value of #Z# ALSO gives the number of the electrons that are conceived to orbit the nuclear core. Why is this so?

In the nucleus itself, there may be as many protons or less AS neutrons, massive particles of zero electronic charge. Interactions between nuclear protons and neutrons, at unfeasibly short nuclear ranges, give rise to the strong nuclear force, the which, at this short range, is strong enough to overcome the electrostatic repulsion between the positively charged protons.

I have written here before that the choice of a negatively charged electronic charge, and a positively charged nuclear charge is a bit unfortunate in that chemists who deal with many electron atoms often get the right magnitude but the wrong charge in their calculations, simply because they counted odd instead of even or even instead of odd. The much smaller company of particle physicists, who are a bit on the weird side anyway, could have coped with a nuclear particle that had a negative electronic charge. Alas we are stuck with the convention.