Oxygen decays to form nitrogen.
3
150
->
19N + e
8
1
This type of nuclear decay is called

Radioactive isotopes ranging from 11O to 26O have also been characterized, all short-lived. The longest-lived radioisotope is 15O with a half-life of 122.24 seconds, while the shortest-lived isotope is 12O with a half-life of 580(30)×10−24 seconds (the half-life of the unbound 11O is still unknown).

it is stable as it is in group 0 which have full outer shells of electrons

level 4 to level 2 : ))