uranium-2381
noun
The common naturally-occurring isotope of uranium, of mass number 238.
- Uranium-238 forms about 99.3 per cent of natural uranium. Unlike uranium-235, it is unable to sustain a nuclear chain reaction, making it unsuitable for use in nuclear power or nuclear weapons. However, the isotope plutonium-239, which is fissile, can be produced by bombarding uranium-238 with low-energy neutrons..
Origin
1920s; earliest use found in London, Edinburgh and Dublin Philosophical Magazine.
uranium-2352
noun
An isotope of uranium, mass number 235, which is able to sustain a nuclear chain reaction, making it suitable for use in nuclear power and nuclear weapons.
- Natural uranium contains only about 0.72% uranium-235, and must be enriched before it can be used as a nuclear fuel or explosive..
Origin
1930s; earliest use found in Science News.