# .What does the atomic number of an element indicate?

Sep 4, 2016

The identity of the element.

#### Explanation:

The atomic number, $Z$, is the number of protons, massive, positively charged nuclear particles. The number $Z$ determines the indentity of the element.

$Z = 1$, the element in $H$, $Z = 2$, the element in $H e$,
$Z = 3$, the element in $L i$,........$Z = 6$, the element in $C$,
$Z = 19$, the element in $K$,......$Z = 26$, the element in $F e$.....

You should not have to remember these, because in every test of chemistry and physics you ever sit, you should be issued a copy of the Perodic Table.