can ignite in air when finely divided. All known thorium isotopes are unstable. The most stable isotope, 232Th, has a half-life of 14.05 billion years,...

This list contains fictional chemical elements, materials, isotopes or subatomic particles that either a) play a major role in a notable work of fiction...

4.5 billion years for different isotopes, making them useful for dating the age of the Earth. The most common isotopes in natural uranium are uranium-238...

concentrations of fissile isotopes in order to sustain a chain reaction. They are also capable of breeding fissile isotopes from fertile materials; a...

is generated. Radon isotopes are the immediate decay products of radium isotopes. The instability of 222Rn, its most stable isotope, makes radon one of...

(praseodymium) isotopes, and the primary products after 142Nd are element Pm (promethium) isotopes. Four of the five stable isotopes are only observationally...

of isotopes of stable atoms. Thomson's device was a crude version of the instrument we now term a mass spectrometer. Neon has three stable isotopes: 20Ne...

to power some spacecraft. Plutonium isotopes are expensive and inconvenient to separate, so particular isotopes are usually manufactured in specialized...

isotopes are lutetium-174 with a half-life of 3.31 years, and lutetium-173 with a half-life of 1.37 years. All of the remaining radioactive isotopes have...

primordial thorium-232, uranium-235, and uranium-238 (223Ra from uranium-235, 226Ra from uranium-238, and the other two from thorium-232). These isotopes nevertheless...