TERMIUM Plus^®

Record 1,  Textual support,  English

Record number: 1, Textual support number: 1 CONT

Although isotopes exhibit nearly identical electronic and chemical behavior, their nuclear behavior varies dramatically. Atomic nuclei consist of protons and neutrons bound together by the strong nuclear force. Because protons are positively charged, they repel each other. Neutrons, which are electrically neutral, allow some separation between the positively charged protons, reducing the electrostatic repulsion and stabilizing the nucleus. For this reason neutrons are necessary for two or more protons to be bound into a nucleus. As the number of protons increases, additional neutrons are needed to form a stable nucleus; for example, although the neutron/proton ratio of³He is 1/2, the neutron/proton ratio of²³⁸U is greater than 3/2. If too many neutrons or too few neutrons are present, the nucleus becomes unstable and subject to nuclear decay.  1, record 1, English, - neutron%2Dproton%20ratio

Record 1,  Textual support,  French

Record 1,  Textual support,  Spanish

Record 2,  Textual support,  English

Record number: 2, Textual support number: 1 CONT

For lighter nuclides a relatively easy way to get a "wrong" n :p ratio is to add a neutron to a stable nuclide(by neutron absorption).  1, record 2, English, - wrong%20n%20%3Ap%20ratio

Record 2,  Textual support,  French

Record number: 2, Textual support number: 1 CONT

Dans le cas des noyaux légers, il est assez facile d'obtenir un rapport N/Z défavorable en ajoutant un neutron à un noyau stable (par absorption de neutrons).  1, record 2, French, - rapport%20N%2FZ%20d%C3%A9favorable

Record 2,  Textual support,  Spanish