Win an All-Access Pass!
Become a new yearly Curie (Radium) or Roentgen (Gold) Radiopaedia Supporter during December and be in the running to win one of four 12-month All-Access Passes. Find out more.


Isotones are atomic species that share the same number of neutrons, and differ in the number of protons.

Examples of isotones include carbon-12, nitrogen-13 and oxygen-14. These atoms all have six neutrons and six, seven and eight protons respectively.

A mnemonic that can be used to differentiate isotones from isotopes and isobars is as follows:

  • Same Z (number of protons) = isotopes
  • Same A (number of nucleons) = isobars
  • Same N (number of neutrons) = isotones


Imaging technology

Article information

rID: 79800
Synonyms or Alternate Spellings:
  • Isotones

ADVERTISEMENT: Supporters see fewer/no ads

Updating… Please wait.

 Unable to process the form. Check for errors and try again.

 Thank you for updating your details.