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How do isotones differ from isotopes?
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isotope
An overview of isotopes.
The primary difference between isotopes and isotones lies in which subatomic particles they share in common:
- Isotopes are species of atoms of the same chemical element that possess the same number of protons (atomic number) but have different numbers of neutrons in their nuclei. Because they have the same atomic number, they occupy the same position in the periodic table and exhibit nearly identical chemical behavior.1
- Isotones are species of atoms or nuclei that have the same number of neutrons but belong to different elements (meaning they have different numbers of protons). For example, chlorine-37 (17 protons, 20 neutrons) and potassium-39 (19 protons, 20 neutrons) are isotones because they both contain 20 neutrons.21
In summary, while isotopes are variations of the same element defined by neutron count, isotones are distinct elements that happen to share an identical neutron count.1