Noun
English Wikipedia has an article on:Isotopes of chlorineWikipedia
chlorine-35 (uncountable)
(physics) The major stable isotope of chlorine, 17Cl, having seventeen protons and eighteen neutrons; it amounts to about 76% of the element in nature
For example, the atomic mass of chlorine-35 to five significant digits is 34.969 u and that of chlorine-37 is 36.966 u. However, the atomic mass in u of each isotope is quite close to its simple mass number (always within 1%). Source: Internet
Deuterium NMR spectra are especially informative in the solid state because of its relatively small quadrupole moment in comparison with those of bigger quadrupolar nuclei such as chlorine-35, for example. Source: Internet
For example, the relative atomic mass of chlorine is 35.453 u, which differs greatly from a whole number due to being made of an average of 76% chlorine-35 and 24% chlorine-37. Source: Internet