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Rutherfordium is a synthetic chemical element; it has symbol Rf and atomic number 104. It is named after physicist Ernest Rutherford. As a synthetic element, it is not found in nature and can only be made in a particle accelerator. It is radioactive; the most stable known isotope, 267 Rf, has a half-life of about 48 minutes.
Group 4 is the second group of transition metals in the periodic table. It contains only the four elements titanium (Ti), zirconium (Zr), hafnium (Hf), and rutherfordium (Rf). ). The group is also called the titanium group or titanium family after its lightest me
Its thermal conductivity (2,200 W/m•K) is five times greater than the most conductive metal (Ag at 429); 300 times higher than the least conductive metal (Pu at 6.74); and nearly 4,000 times that of water (0.58) and 100,000 times that of air (0.0224). This high thermal conductivity is used by jewelers and gemologists to separate diamonds from ...
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.
2, and is remarkable in having direct chemical bonds between two notoriously unreactive atoms, xenon and gold, with xenon acting as a transition metal ligand. The compound Xe 2 Sb 2 F 11 contains a Xe–Xe bond, the longest element-element bond known (308.71 pm = 3.0871 Å). The most common oxide of xenon (XeO 3) is strongly acidic.
For example, no significant change in blood formula, body and organ weights, and food consumption could be detected for rats which ingested up to 15 μg of technetium-99 per gram of food for several weeks. [99] In the body, technetium quickly gets converted to the stable TcO − 4 ion, which is highly water-soluble and quickly excreted. The ...
Marignac suspected that ytterbia was a compound of a new element that he called "ytterbium". [13] [27] [32] [33] [34] In 1907, the French chemist Georges Urbain separated Marignac's ytterbia into two components: neoytterbia and lutecia. Neoytterbia later became known as the element ytterbium, and lutecia became known as the element lutetium.
A metalloid is an element that possesses a preponderance of properties in between, or that are a mixture of, those of metals and nonmetals, and which is therefore hard to classify as either a metal or a nonmetal. This is a generic definition that draws on metalloid attributes consistently cited in the literature.