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Very few properties of rutherfordium or its compounds have been measured; this is due to its extremely limited and expensive production [70] and the fact that rutherfordium (and its parents) decays very quickly. A few singular chemistry-related properties have been measured, but properties of rutherfordium metal remain unknown and only ...
Rutherfordium is expected to be a solid under normal conditions and have a hexagonal close-packed crystal structure (c / a = 1.61), similar to its lighter congener hafnium. [33] It should be a metal with density ~17 g/cm 3. [44] [45] The atomic radius of rutherfordium is expected to be ~150 pm.
All of the stable alkali metal halides have the formula MX where M is an alkali metal and X is a halogen. They are all white ionic crystalline solids that have high melting points. [5] [84] All the alkali metal halides are soluble in water except for lithium fluoride (LiF), which is insoluble in water due to its very high lattice enthalpy.
Most definitions of the term 'refractory metals' list the extraordinarily high melting point as a key requirement for inclusion. By one definition, a melting point above 4,000 °F (2,200 °C) is necessary to qualify, which includes iridium, osmium, niobium, molybdenum, tantalum, tungsten, rhenium, rhodium, ruthenium and hafnium. [2]
The Joint Institute for Nuclear Research in Dubna (then USSR, today Russia) named element 104 kurchatovium (Ku) in honor of Igor Kurchatov, father of the Soviet atomic bomb, while the University of California, Berkeley, US, named element 104 rutherfordium (Rf) in honor of Ernest Rutherford.
With its similar properties to and lower cost than rhodium, electric contacts are a major use of ruthenium. The ruthenium plate is applied to the electrical contact and electrode base metal by electroplating or sputtering. Osmium is a hard but brittle metal that remains lustrous even at high temperatures. It has a very low compressibility.
The rare-earth elements (REE), also called the rare-earth metals or rare earths, and sometimes the lanthanides or lanthanoids (although scandium and yttrium, which do not belong to this series, are usually included as rare earths), [1] are a set of 17 nearly indistinguishable lustrous silvery-white soft heavy metals.
Rutherfordium (104 Rf) is a synthetic element and thus has no stable isotopes. A standard atomic weight cannot be given. The first isotope to be synthesized was either 259 Rf in 1966 or 257 Rf in 1969. There are 17 known radioisotopes from 252 Rf to 270 Rf (three of which, 266 Rf, 268 Rf, and 270 Rf, are unconfirmed) and several isomers.