Question

use this information to write the element in isotope notation. 11 p+, 11 e-, 12 n0
11
na
22.99
what is the atomic number?
? na

Explanation:

Step1: Recall atomic number definition

The atomic number ($Z$) is equal to the number of protons in an atom.

Step2: Identify number of protons

Given there are 11 protons ($p^{+}$). So the atomic number $Z = 11$.

Answer:

11