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This is a list of prices of chemical elements. Listed here are mainly average market prices for bulk trade of commodities. Data on elements' abundance in Earth's crust is added for comparison. As of 2020, the most expensive non-synthetic element by both mass and volume is rhodium.
Liquid helium is a physical state of helium at very low temperatures at standard atmospheric pressures. Liquid helium may show superfluidity . At standard pressure, the chemical element helium exists in a liquid form only at the extremely low temperature of −269 °C (−452.20 °F; 4.15 K).
The average price of liquid helium in North America in 2013 was around $6 per liter and represents the lower end of the price range; Europe with around $10 per liter is in the middle, whereas Latin America and Asia expends the highest band range of $13–15 per liter. [5]
Price at auction, historically about $100 per litre ($450/imp gal), reached as high as $2,000 per litre ($9,100/imp gal). [35] Since then, demand for helium-3 has declined to about 6,000 litres (1,300 imp gal; 1,600 US gal) per year due to the high cost and efforts by the DOE to recycle it and find substitutes.
The helium atoms are immobilized in the snowball by polarization. Neutral metallic atoms in liquid helium are also surrounded by a bubble caused by electron repulsion. They have typical sizes ranging from 10 to 14 Å diameter. [51] Free electrons in liquid helium are enclosed in a bubble 17 Å in diameter.
Pages in category "Liquid helium" The following 6 pages are in this category, out of 6 total. This list may not reflect recent changes. ...
Terrestrial helium consists almost exclusively (all but ~2ppm) [16] of 4 He. 4 He's boiling point of 4.2 K is the lowest of all known substances except 3 He. When cooled further to 2.17 K, it becomes a unique superfluid with zero viscosity. It solidifies only at pressures above 25 atmospheres, where it melts at 0.95 K.
This condensation occurs in liquid helium-4 at a far higher temperature (2.17 K) than it does in helium-3 (2.5 mK) because each atom of helium-4 is a boson particle, by virtue of its zero spin. Helium-3, however, is a fermion particle, which can form bosons only by pairing with itself at much lower temperatures, in a weaker process that is ...