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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. Listed here are mainly average market prices for bulk trade of commodities. Data on elements' abundance in Earth's crust is added for comparison.
Iridium is a chemical element; it has symbol Ir and atomic number 77. A very hard, brittle, silvery-white transition metal of the platinum group, it is considered the second-densest naturally occurring metal (after osmium) with a density of 22.56 g/cm 3 (0.815 lb/cu in) as defined by experimental X-ray crystallography.
From 2011 the European Union started to phase out refrigerants with a global warming potential (GWP) of more than 150 in automotive air conditioning (GWP = 100-year warming potential of one kilogram of a gas relative to one kilogram of CO 2) such as the refrigerant HFC-134a (known as R-134a in North America) which has a GWP of 1526. [50]
A coolant is a substance, typically liquid, that is used to reduce or regulate the temperature of a system. An ideal coolant has high thermal capacity, low viscosity, is low-cost, non-toxic, chemically inert and neither causes nor promotes corrosion of the cooling system. Some applications also require the coolant to be an electrical insulator.
The exact number of cans per pound can't be quantified due to different measurements. Depending on the brand, estimates show there are usually 32 to 35 cans per pound. For smaller, more common 12 ...
The strength and high-temperature stability of refractory metals make them suitable for hot metalworking applications and for vacuum furnace technology. Many special applications exploit these properties: for example, tungsten lamp filaments operate at temperatures up to 3073 K, and molybdenum furnace windings withstand 2273 K.
Osmium is one of the least abundant stable elements in Earth's crust, with an average mass fraction of 50 parts per trillion in the continental crust. [55] Osmium is found in nature as an uncombined element or in natural alloys; especially the iridium–osmium alloys, osmiridium (iridium rich), and iridosmium (osmium rich). [48]
Other demands include cost, weight, reliability, and durability of the cooling system itself. Conductive heat transfer is proportional to the temperature difference between materials. If engine metal is at 250 °C and the air is at 20 °C, then there is a 230 °C temperature difference for cooling. An air-cooled engine uses all of this difference.