Actinide elements principal isotopes

Symbol Cf atomic number 98 atomic weight 251 (the principal isotope) californium is a transuranium radioactive actinide element electron configuration [Rn]5/i°7s2 valence state +3 most stable isotope Cf, half-life 800 years isotope properties are presented below ... 

The actinide elements (which are all radioactive) up to Z = 103 are listed in Table 20-1 along with some of their properties. The principal isotopes that can be obtained in macroscopic amounts are listed in Table 20-2. The significance of the term actinide series is justified by the overall agreement of the chemistry of these elements with that concept, although it is not as clearly justified as is the lanthanide concept. Note in Table 20-1 that some irregular variation in the 5f/6d electron distribution does occur. 

The actinide elements, all of whose isotopes are radioactive, are listed in Table 28-1, together with some of their properties. The principal isotopes obtained in macroscopic amounts are given in Table 28-2. 

The principal application of the actinide elements is in the production of nuclear energy. Although this is by far the most important use for any of the actinide elements, a surprising number of other uses have been found. These include the use of short-lived actinide isotopes as portable power supplies for satellites in ionization smoke detectors in the therapy of cancer in neutron radiography in mineral prospecting and oil-well logging as neutron sources in nuclear reactor start-up and as neutron sources in a variety of analytical procedures, the most important of which are neutron activation analysis and heavy-ion desorption mass spectroscopy. 

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