What are the numbers of the subatomic particles in Au?

1 Answer
Sep 25, 2016

Got a Periodic Table? Mine says that for elemental gold, #Z=79#.

Explanation:

#Z# refers to the number of positively charged nuclear particles. The number defines the identity of the element. If there are 79 positively charged nuclear particles, there MUST be 79 electrons whizzing around nucleus in the neutral atom.

The typical gold nucleus is the #""^197Au# isotope. As well as the #79# protons, there must be #197-79=118" neutrons"#, which are massive nuclear particles of ZERO electonic charge.

And thus for the #""^197Au# isotope, there are necessarily 79 protons, 118 neutrons, and 79 electrons.