Mendeleev
Periodic table · chemistry · physics
Element story

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.

Keep exploring

→ Oganesson · Atomic structure · Periodic trends

118OgOganesson
Oganesson · Og · Z = 118

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.

Understanding the element

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.

Where do we encounter it?

In practice, it turns up most often in scientific research.

What its position in the table tells us

Oganesson sits in period 7, group 18 and the P block. That location is useful because neighbouring elements often share trends in valence electrons, oxidation states and bonding behaviour.