One of only two cis-uranic elements with no stable isotopes, it (technetium) had to be synthesised to be discovered (hence the name). The other one is protactinium. @ndbrning The first long-lived isotope of protactinium was discovered by Otto Hahn and Lise Meitner in 1917. 80 years later...
Julesium is a hypothetical Yoso element with the atomic number y330 and the symbol Jul. It is named after Gary Jules. Julesium is possibly a colourless solid at room temperature. Julesium is radioactive and has no stable isotopes. Its most stable isotope
Like all chemical elements with an atomic number greater than 82, Armenium has no stable isotopes. The most stable of these, 938Arm has a half-life of about 42 picoseconds (4.2x10-11 seconds). Positive Periodic Table (Complex/Negative/Antimatter/Zetonic/Monopole/Fanonium/Fandonium) -0 0...
abundant of the halogens inEarth’s crust. The percentages of the halogens in theigneous rocksof Earth’s crust are 0.06 fluorine, 0.031 chlorine, 0.00016 bromine, and 0.00003 iodine. Astatine and tennessine do not occur in nature, because they consist of only short-lived radioactiveisotopes....
ofisotopesof every element—atoms with the same atomic number but different atomic weights. The chemical properties of the isotopes of an element are essentially the same, and all the isotopes of an element occupy the same place in the periodic system in spite of their differences in atomic ...
Proof that this was true of the elements generally could only be obtained by direct atomic analysis. This was achieved by the mass-spectrograph, and with it the search for isotopes has been carried on continuously for the past fifteen years. Wide differences of properties among the elements ...
Lithium3LiAr(Li) = 6.941(2)IsotopeAtomic mass Mole fraction in L-SVEC Li2CO3[2,26]6Li6.015 1223(5) u0.075 91(20)7Li7.016 0041(5) u0.924 09(20)The basis for relative abundance measurements of Li isotopes is IAEA isotopic reference materialL-SVEC (NIST RM 8545) Li2CO3with an assigned ...
et al. Rapid extraction of short-lived isotopes from a buffer gas cell for use in gas-phase chemistry experiments. Part I: off-line studies with 219Rn and 221Fr. Nucl. Instrum. Methods Phys. Res. A Accel. Spectrom. Detect. Assoc. Equip. 995, 165090 (2021). Article Google Scholar ...
units (amu). Even though each atom has roughly a whole number of atomic mass units, you will notice that the atomic mass on the periodic table is a decimal; that's because the number is a weighted average of the various naturally-occurring isotopes of an element based on their abundance....
Ellison says, "There's only a very low probability that the two isotopes will interact to form a compound nucleus. To make it happen, we need very intense beams of calcium on the target, and then we need a detector that can sift through the many unwanted reaction products to find and ...