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...

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...

of neptunium-237, these are the five most stable isotopes of radium. All other 27 known radium isotopes have half-lives under two hours, and the majority...

Platinum also has 38 synthetic isotopes ranging in atomic mass from 165 to 208, making the total number of known isotopes 44. The least stable of these...

48 MeV of energy. The known isotopes of silicon range in mass number from 22 to 46. The most common decay mode of the isotopes with mass numbers lower than...

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

seven stable isotopes and two long-lived radioactive isotopes. More than 40 unstable xenon isotopes undergo radioactive decay, and the isotope ratios of...

stable isotopes of potassium can be laser cooled and used to probe fundamental and technological problems in quantum physics. The two bosonic isotopes possess...

than 15 minutes. The isotopes of cobalt range in atomic weight from 50 u (50Co) to 73 u (73Co). The primary decay mode for isotopes with atomic mass unit...

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...

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

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

artificial isotopes of zirconium have been synthesized, ranging in atomic mass from 77 to 114. 93Zr is the longest-lived artificial isotope, with a half-life...

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, or about...

The isotopes of ytterbium range from 149Yb to 187Yb. The primary decay mode of ytterbium isotopes lighter than the most abundant stable isotope, 174Yb...

elements. At least 40 isotopes of hafnium have been observed, ranging in mass number from 153 to 192. The five stable isotopes have mass numbers ranging...

isotopes, and the primary products after are erbium isotopes. Natural holmium consists of one primordial isotope, holmium-165; it is the only isotope...

hydrogen or the trihydrogen cation. Hydrogen has three naturally occurring isotopes, denoted 1 H, 2 H and 3 H. Other, highly unstable nuclei (4 H to 7 H) have...

and iron, so as to recycle long-lived waste isotopes such as neptunium-237 into shorter-lived isotopes more useful as nuclear fuel. One neptunium-based...

support is alumina. Commercial catalysts are often based on molybdenum and ruthenium. Well-defined organometallic compounds have mainly been investigated for...

68 (erbium) isotopes, and the primary products after are element 70 (ytterbium) isotopes. Thulium-169 is thulium's only primordial isotope and is the only...

possible to produce exotic helium isotopes, which rapidly decay into other substances. The shortest-lived heavy helium isotope is the unbound helium-10 with...

isotopes primarily undergo beta plus decay to isotopes of arsenic, and isotopes heavier than the stable isotopes undergo beta minus decay to isotopes...

Because of the specificity of its uptake by the human body, radioactive isotopes of iodine can also be used to treat thyroid cancer. Iodine is also used...

unstable isotopes of elements that undergo decay and thereby emit ionizing radiation, which is harmful to humans and the environment. Different isotopes emit...

percent upon melting. Gallium has 30 known isotopes, ranging in mass number from 60 to 89. Only two isotopes are stable and occur naturally, gallium-69...

always is to be mentioned. Naturally occurring lanthanum is made up of two isotopes, the stable 139 La and the primordial long-lived radioisotope 138 La. 139...

isotopes lighter than 141Pr is positron emission or electron capture to isotopes of cerium, while that of heavier isotopes is beta decay to isotopes of...

isotope in the Universe, taking into account the elemental abundance of tantalum and isotopic abundance of 180mTa in the natural mixture of isotopes (and...

call these elements with complete chemical identity "isotopes". The problem of placing isotopes in the periodic table had arisen beginning in 1900 when...