What is the 4th element on the periodic table

Beryllium is the fourth element of the periodic table.

Explanation:

Beryllium has four protons, so has an atomic number of four. The atomic number depends on the place it has in the periodic table. For example, hydrogen is the first element with one proton in its nucleus and an atomic number of one. Helium is the second element with two protons in its nucleus and an atomic number or two. It goes on. After helium is lithium, then beryllium.