# What is the integer related to the number of electrons under an atom's control?

May 20, 2017

The atomic number, $Z$, specifies the ultimate charge of an atom or ion.

#### Explanation:

$Z$, the atomic number, specifies precisely how many massive, positively charged particles are present in the atom's nucleus, and this defines the identity of the atom:

Z=1,H;Z=2,He;Z=3,Li....;Z=23,V;............

In general for every nuclear charge, there is an electronic charge, due to an equal number of electrons that are conceived to whizz about the nuclear core. That is the number of electrons and protons ARE EQUAL for a neutral element.

But a given element, can have more or less electrons than $Z$. If the number of electrons $> Z$, then we have an anion; and thus you should be able to tell me the number of electrons in common anions such as ${O}^{2 -} , {X}^{-} , {P}^{3 -}$, and in common cations, $M {n}^{2 +} , F {e}^{3 +} , N {i}^{2 +}$, where there are LESS electrons than $Z$. Capisce?

For another answer that addresses $\text{formal charge}$, see this linky.