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Isotopes, isobars, isotones
Beginner
Same Z, same A, same N.
Isotopes: same Z, different N (¹H, ²H); isobars: same A (¹⁴C, ¹⁴N); isotones: same N.
Uranium-235 and -238 are isotopes.
Chemical properties follow Z.
In more detail
Isotopes have the same number of protons but different numbers of neutrons. Isobars have the same mass number, and isotones have the same number of neutrons.
Real-world uses
- Carbon-14 is used for dating, and carbon-12 is the standard for atomic mass.
- Medical isotopes are chosen for their specific properties.
- Medical physicists choose a radioactive isotope of an element, such as iodine-131, for diagnosis or treatment.
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Frequently asked questions
Do isotopes behave chemically the same?
Largely yes, since chemistry depends on electrons, though small mass differences matter slightly.
Are all isotopes radioactive?
No. Many are stable, while others decay.
What is the difference between isotopes and isobars?
Isotopes share the same protons but differ in neutrons, while isobars share the same mass number but have different protons.
Related topics in Atomic & Nuclear Physics
Electron configuration · Atomic mass unit · Nucleus composition · Nuclear size · Nuclear density · Mass defect