The chemical Série of the actinides includes/understands the chemical elements periodic table being located between the Actinium and the Lawrencium, thus having a Atomic number between 89 and 103 included.
The actinides all are of the radioactive elements and draw their name from the Actinium (Z=89), a Heavy metal, because they have close chemical properties. The Uranium and the Thorium, which are relatively abundant in a natural state because of very long Demi-vie of their most stable Isotope S, are actinides. The actinides include/understand artificial elements, the Transuranien S, heavier than uranium: they are generated by captures of Neutron S which were not followed of fissions.
The actinide produces most abundantly is the Plutonium, with at the head its principal isotope fissile plutonium-239, itself . But the engines generate, in less quantity, other actinides which are called “minors” for this reason. The principal ones are the Neptunium -237, the Américium -241 and 243 and the Curium -244 and 245. The minor actinides constitute with the Plutonium most of the Radioactive waste with high activity and long life of life (HALV), i.e. waste of the nuclear industry most dangerous.
They have chemical characteristics similar to those of the Lanthanide S, when they are with the same oxidation step. Contrary to the Lanthanide S, the light actinides can be stable with the oxidation steps +5 (Pa, U, Np, Pu, Am) and +6 (U, Np, Pu, Am). This greater facility of ionization (of actinides compared to the Lanthanide S) is explained by the fact why the orbital of valence 5f of actinides, are less interns than the 4f of the Lanthanide S, because more écrantées by the electrons of heart. The actinides with the same oxidation step are similar chemical between them, except notable for Pa (V).
The isotopes of the transuranic elements often have a very short Demi-vie, with the notable exceptions, of some isotopes of Np, Pu, Am and Cm produced in ponderable quantities in the nuclear reactors.
In the periodic table, the actinides are placed under the Lanthanide S, these two series being generally under the principal part of the table, with the manner of a footnote.
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