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Rhenium is a chemical element; it has symbol Re and atomic number 75. It is a silvery-gray, heavy, third-row transition metal in group 7 of the periodic table. With an estimated average concentration of 1 part per billion (ppb), rhenium is one of the rarest elements in the Earth's crust. It has one of the highest melting and boiling points of ...
Group 7, numbered by IUPAC nomenclature, is a group of elements in the periodic table.It contains manganese (Mn), technetium (Tc), rhenium (Re) and bohrium (Bh). This group lies in the d-block of the periodic table, and are hence transition metals.
Rhenium compounds are compounds formed by the transition metal rhenium (Re). Rhenium can form in many oxidation states , and compounds are known for every oxidation state from -3 to +7 except -2, although the oxidation states +7, +4, and +3 are the most common. [ 1 ]
Rhenium is a chemical element with the symbol Re and atomic number 75. It is a silvery-white, heavy, third-row transition metal in group 7 of the periodic table. With an estimated average concentration of 1 part per billion (ppb), rhenium is one of the rarest elements in the Earth's crust.
Refractory metals have high melting points, with tungsten and rhenium the highest of all elements, and the other's melting points only exceeded by osmium and iridium, and the sublimation of carbon. These high melting points define most of their applications. All the metals are body-centered cubic except rhenium which is hexagonal close-packed.
The period 6 and 7 transition metals also add core (n − 2)f 14 electrons, which are omitted from the tables below. The p orbitals are almost never filled in free atoms (the one exception being lawrencium due to relativistic effects that become important at such high Z), but they can contribute to the chemical bonding in transition metal ...
Many other compounds with quadruple bonds between transition metal atoms have been described, often by Cotton and his coworkers. Isoelectronic with the dirhenium compound is the salt K 4 [Mo 2 Cl 8] (potassium octachlorodimolybdate). [7] An example of a ditungsten compound with a quadruple bond is ditungsten tetra(hpp).
Transition metal carbyne complexes are most common for the early transition metals, especially niobium, tantalum, molybdenum, tungsten, and rhenium. They can also have low-valence metals as well as high-valence metals. Protonation of a Re(I) vinylidene complex to give the corresponding cationic Re(V) carbyne derivative.