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Graphs of abundance vs atomic number. Abundance (atom fraction) of the chemical elements in Earth's upper continental crust as a function of atomic number; [5] siderophiles shown in yellow. Graphs of abundance against atomic number can reveal patterns relating abundance to stellar nucleosynthesis and geochemistry.
At least 17,000 metric tons of fluorine are produced each year. It costs only $5–8 per kilogram as uranium or sulfur hexafluoride, but many times more as an element because of handling challenges. Most processes using free fluorine in large amounts employ in situ generation under vertical integration. [186]
Fluorine is primarily carried by rivers to the oceans, where it can have a residence time of about 500,000 years. Fluorine can be removed from the ocean by deposition of terrigenous or authigenic sediments, or subduction of the oceanic lithosphere. The fluorine cycle is the series of biogeochemical processes through which fluorine moves through ...
Fluorite mining (the main source of fluorine) was estimated in 2003 to be a $550 million industry, extracting 4.5 million tons per year. [4] Mined fluorite is separated into two main grades, with about equal production of each. Acidspar is at least 97% CaF 2; metspar is much lower purity, 60–85%.
Fluorite (CaF 2), also called fluorspar, is the main source of commercial fluorine. Fluorite is a colorful mineral associated with hydrothermal deposits. It is common and found worldwide. China supplies more than half of the world's demand and Mexico is the second-largest producer in the world. [citation needed] The United States produced most ...
Carbon dioxide is absorbed from the atmosphere at the ocean's surface at an exchange rate which varies locally and with time [32] but on average, the oceans have a net absorption of around 2.9 Pg (equivalent to 2.9 billion metric tonnes) of carbon from atmospheric CO 2 per year. [33]
The geology of Mercury is the scientific study of the surface, crust, and interior of the planet Mercury. It emphasizes the composition, structure, history, and physical processes that shape the planet. It is analogous to the field of terrestrial geology. In planetary science, the term geology is used in its broadest sense to mean the study of ...
Contents. Mercury (planet) Surface temp. Mercury is the first planet from the Sun and the smallest in the Solar System. In English, it is named after the ancient Roman god Mercurius (Mercury), god of commerce and communication, and the messenger of the gods. Mercury is classified as a terrestrial planet, with roughly the same surface gravity as ...