* Atomic Number: The atomic number of an element tells you how many protons are in its nucleus.

* Periodic Table: The elements are arranged on the periodic table in order of increasing atomic number.

To find the element with an atomic number one greater than platinum, you need to know platinum's atomic number. Platinum (Pt) has an atomic number of 78.

Therefore, the element with an atomic number one greater than platinum is gold (Au), which has an atomic number of 79.