Oganesson
Atomic number 118 means that every Oganesson nucleus contains 118 protons. That proton count is the element's identity: change it and you no longer have Oganesson.
Start with the nucleus
Atomic number 118 means that every Oganesson nucleus contains 118 protons. That proton count is the element's identity: change it and you no longer have Oganesson.
Oganesson (Og) is chemical element 118. It belongs to the noble gases, and its reference state at room temperature is not firmly established. Those basic facts are a useful starting point for its chemistry and applications.
In practice, it turns up most often in scientific research.
See the atom
Conceptual visual: electron shells are a learning aid, not a literal picture of quantum orbitals.
What this number means
Atomic number 118 means that every Oganesson nucleus contains 118 protons. That proton count is the element's identity: change it and you no longer have Oganesson.