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Rhenium has one stable isotope, rhenium-185, which nevertheless occurs in minority abundance, a situation found only in two other elements (indium and tellurium). Naturally occurring rhenium is only 37.4% 185 Re, and 62.6% 187 Re, which is unstable but has a very long half-life (~10 10 years).
Rhenium was the last element to be discovered having a stable isotope. The existence of a yet undiscovered element at this position in the periodic table had been predicted by Henry Moseley in 1914. In 1925 they reported that they detected the element in platinum ore and in the mineral columbite. They also found rhenium in gadolinite and ...
They also found rhenium in gadolinite and molybdenite. [5] In 1928 they were able to extract 1 gram of the element by processing 660 kg of molybdenite. In 2020 a memorial medal of the discovery was issued by ISTR (art-designer: Igor Petrov).
The nuclides found naturally comprise not only the 286 primordials, but also include about 52 more short-lived isotopes (defined by a half-life less than 100 million years, too short to have survived from the formation of the Earth) that are daughters of primordial isotopes (such as radium from uranium); or else are made by energetic natural ...
Rhenium resembles manganese chemically and is obtained as a by-product of molybdenum and copper ore's extraction and refinement. Rhenium shows in its compounds a wide variety of oxidation states ranging from −1 to +7. Discovered in 1925, rhenium was the last stable element to be discovered. It was named after the river Rhine in Europe.
Naturally occurring rhenium (75 Re) is 37.4% 185 Re, which is stable (although it is predicted to decay), and 62.6% 187 Re, which is unstable but has a very long half-life (4.12×10 10 years). [4] Among elements with a known stable isotope, only indium and tellurium similarly occur with a stable isotope in lower abundance than the long-lived ...
Now, an international team of scientists have analyzed the first faintest galaxies (which existed in the universe’s first billion or so years) and identified certain dwarf galaxies that are ...
Neon's abundance in the universe is about 1 part in 750 by mass; in the Sun and presumably in its proto-solar system nebula, about 1 part in 600. [ citation needed ] The Galileo spacecraft atmospheric entry probe found that in the upper atmosphere of Jupiter, the abundance of neon is reduced (depleted) by about a factor of 10, to a level of 1 ...