Question

How does the number of valence electrons vary with atomic number?

Answer 1

The number of valence electrons increases sequentially with `Z`.

Explanation:

Read all the answers in this [thread.](https://socratic.org/questions/what-kind-of-charge-does-oxygen-have`174826) The identity of an element depends on`Z#, the atomic number, which is the number of positively charged particles in the element's nucleus.

However, if there are `Z` positive charges, in the NEUTRAL atom, there must necessarily be `Z` negative charges, supplied by `Z` electrons, all whizzing about the nucleus. Conservation of charge is a fundamental principle of Chemistry (and Physics).