Search results
Results from the WOW.Com Content Network
Na, and one each for 24 Na, 26 Na, and 32 Na). 23 Na is the only stable (and the only primordial) isotope. It is considered a monoisotopic element and it has a standard atomic weight of 22.989 769 28 (2). Sodium has two radioactive cosmogenic isotopes (22 Na, with a half-life of 2.6019(6) years; [nb 1] and 24 Na, with a half-life of 14.9560(15) h).
sodium-18: 1.34 lithium-10m2: 1.35 lithium-10: 2.0 beryllium-13: 2.7 helium-7: ... half-life 10 15 years 10 24 seconds hafnium-174: 70 2.2 vanadium-50: 140 4.4 10 18 ...
Two radioactive, cosmogenic isotopes are the byproduct of cosmic ray spallation: 22 Na has a half-life of 2.6 years and 24 Na, a half-life of 15 hours; all other isotopes have a half-life of less than one minute. [17] Two nuclear isomers have been discovered, the longer-lived one being 24m Na with a half-life
Aluminium can capture a neutron and generate radioactive sodium-24, which has a half life of 15 hours [9] [10] and a beta decay energy of 5.514 MeV. [11] The activation of a number of test target elements such as sulfur, copper, tantalum, and gold have been used to determine the yield of both pure fission [12] [13] and thermonuclear weapons. [14]
One of the primordial nuclides is tantalum-180m, which is predicted to have a half-life in excess of 10 15 years, but has never been observed to decay. The even-longer half-life of 2.2 × 10 24 years of tellurium-128 was measured by a unique method of detecting its radiogenic daughter xenon-128 and is the longest known experimentally measured ...
A chart or table of nuclides maps the nuclear, or radioactive, behavior of nuclides, as it distinguishes the isotopes of an element.It contrasts with a periodic table, which only maps their chemical behavior, since isotopes (nuclides that are variants of the same element) do not differ chemically to any significant degree, with the exception of hydrogen.
The main column shows times in seconds (31,556,926 seconds = 1 tropical year); a second column showing half-life in more usual units (year, day) is also provided. Entries starting with a ">" indicates that no decay has ever been observed, with null experiments establishing lower limits for the half-life.
However, the short half-life of sodium-24 (15 h) [8]: 25 would mean that the radiation would not spread far enough to be a true doomsday weapon. [7] [9] A cobalt bomb was first suggested by Leo Szilard in 1950. He publicly sounded the alarm against the possible development of salted thermonuclear bombs capable of annihilating mankind on a ...