![cover image](https://wikiwandv2-19431.kxcdn.com/_next/image?url=https://upload.wikimedia.org/wikipedia/commons/thumb/f/f2/Yuri_Oganessian.jpg/640px-Yuri_Oganessian.jpg&w=640&q=50)
Oganesson
element with the atomic number of 118 / From Wikipedia, the free encyclopedia
Oganesson is a synthetic chemical element with symbol Og and atomic number 118. Oganesson has the highest atomic number and highest atomic mass of all known elements. The radioactive oganesson atom is very unstable, and since 2005, only five (possibly six) atoms of the isotope Oganesson-294 have been created.
![Thumb image](http://upload.wikimedia.org/wikipedia/commons/thumb/f/f2/Yuri_Oganessian.jpg/640px-Yuri_Oganessian.jpg)