Question

How can you get determine an atomic number?

Answer 1

You can look at the periodic table.

Explanation:

The atomic number of any element is the number of protons one atom has in its nucleus. The periodic table of elements shows each element's atomic number; it is basically arranged in order of increasing atomic number.

For example, the atomic number of hydrogen (H) is 1, the atomic number of boron (B) is 5, etc.

Answer 2

The element number in the element box on the periodic table is the Atomic Number.

Explanation:

The Atomic Number of an element defines the number of protons in the nucleus of the specified element. For Oxygen, Atomic Number is 8 which means that all Oxygen atoms have 8 protons in their nuclei. For Uranium, the Atomic Number is 92 => `92p^+` in the Uranium nucleus.

Also, the atomic number is the basis for the 'Periodic Law' ...
"The chemical and physical properties of the elements are a periodic function of their Atomic Numbers."