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Francium-223 also has a shorter half-life than the longest-lived isotope of each synthetic element up to and including element 105, dubnium. [8] Francium is an alkali metal whose chemical properties mostly resemble those of caesium. [8] A heavy element with a single valence electron, [9] it has the highest equivalent weight of any element. [8]
Of course, one could argue that the solubility of francium salts cannot be measured in practice due to the tiny amounts of francium involved, but the periodic table has been pretty good at predicting many things in the past.
However, it would appear that francium perchlorate has been formed, as it coprecipitates with caesium perchlorate, and several other insoluble francium salts are similarly known (Hyde, E.K., Radiochemical Methods for the Isolation of Element 87 (Francium), J. Am. Chem. Soc., 1952, 74, 4181) The article also quotes a value for the Pauling ...
Its first ionization energy is predicted to be 429.4 kJ/mol, which would be lower than those of all known elements except for the alkali metals potassium, rubidium, caesium, and francium: this value is even lower than that of the period 8 alkali metal ununennium (463.1 kJ/mol).
Has no known biological role; as it is radioactive with a short half-life, it is very rare and is seldom present for long. [11] Radioactive. [11] protactinium: 91: 1b: Has no known biological role; as it is radioactive with a short half-life, it is very rare and is seldom present for long. [11] Both toxic and highly radioactive. radium: 88: 1bc
Health assessment has been separated by authors from physical assessment to include the focus on health occurring on a continuum as a fundamental teaching. [8] In the healthcare industry it is understood health occurs on a continuum, so the term used is assessment but may be preference by the speciality's focus such as nursing, physical therapy, etc.
Deloitte CEO Jason Girzadas discusses the issues that have CEOs will be talking about in 2025.
Francium's melting point was estimated to be around 8.0 °C (46.4 °F); a value of 27 °C (81 °F) is also often encountered. The melting point is uncertain because of the element's extreme rarity and radioactivity ; a different extrapolation based on Dmitri Mendeleev 's method gave 20 ± 1.5 °C (68.0 ± 2.7 °F).