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1 Chart. 2 See also. 3 Notes. ... Per-kilogram prices of some synthetic radioisotopes range to trillions of dollars. ... Helium: 0.0001785: 0.008 ...
Of course, cost per kg is not the only important factor in material selection. An important concept is 'cost per unit of function'. For example, if the key design objective was the stiffness of a plate of the material, as described in the introductory paragraph above, then the designer would need a material with the optimal combination of ...
The amount of mass that can be lifted by hydrogen in air per unit volume at sea level, equal to the density difference between hydrogen and air, is: (1.292 - 0.090) kg/m 3 = 1.202 kg/m 3. and the buoyant force for one m 3 of hydrogen in air at sea level is: 1 m 3 × 1.202 kg/m 3 × 9.8 N/kg= 11.8 N
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).
To ensure that the revenue from future sales would amortize the cost, the Secretary of the Interior raised the price of high purity helium from $12 per thousand cubic feet to $35. [1] [4] This price jump was an incentive for private companies to enter the market and sell helium at lower prices. [1] [3] [4] By 1970, it also became evident that ...
Atomic number (Z): 2: Group: group 18 (noble gases) Period: period 1: Block s-block Electron configuration: 1s 2: Electrons per shell: 2: Physical properties; Phase at STP: gas: Boiling point
This page uses the meta infobox {{Infobox isotopes (meta)}} for the element isotopes infobox.. This infobox contains the table of § Main isotopes, and the § Standard atomic weight.
It is used in deep commercial diving, during the deep phase of dives carried out using technical diving techniques, [1] [2] and in advanced recreational diving. [3] [4] The helium is included as a substitute for some of the nitrogen, to reduce the narcotic effect of the breathing gas at depth and to reduce the work of breathing. With a mixture ...