Chemistry · Ch 4 — Structure of Atom
Isotones
Isotones
Isotones are atoms of different elements whose nuclei happen to contain exactly the same number of neutrons, even though their atomic numbers and mass numbers are both different. For example, has neutrons, and has neutrons as well — boron-11 and carbon-12 are therefore isotones of one another, sharing a neutron count while differing in both Z and A. Isotopes, isobars and isotones are thus three distinct ways in which nuclides of different (or the same) elements can resemble one another numerically: isotopes share Z, isobars share A, and isotones share N. These relat …
Table 4.4 — an isotone pair, both with N = 6 neutrons:
¹¹B: Z = 5, A = 11, neutrons N = A − Z = 6.
¹²C: Z = 6, A = 12, neutrons N = 6.
Both nuclei contain exactly 6 neutrons even though boron and carbon have different atomic numbers and mass numbers. (The chapter notes that more aspects of nuclides are tak …