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  2. Liquid helium - Wikipedia

    en.wikipedia.org/wiki/Liquid_helium

    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).

  3. Densities of the elements (data page) - Wikipedia

    en.wikipedia.org/wiki/Densities_of_the_elements...

    2 He helium-4; Hoffer et al. 0.19085 ... formula weight = 222 Notes ... The suggested values for liquid densities refer to "at the melting point (m.p.)" by default ...

  4. Lifting gas - Wikipedia

    en.wikipedia.org/wiki/Lifting_gas

    The amount of mass that can be lifted by helium in air at sea level is: (1.292 - 0.178) kg/m 3 = 1.114 kg/m 3. and the buoyant force for one m 3 of helium in air at sea level is: 1 m 3 × 1.114 kg/m 3 × 9.8 N/kg= 10.9 N. Thus hydrogen's additional buoyancy compared to helium is: 11.8 / 10.9 ≈ 1.08, or approximately 8.0%

  5. The world is running out of helium. Here's why doctors are ...

    www.aol.com/news/world-running-helium-heres-why...

    Mahesh estimates that an MRI machine uses 10,000 liters of liquid helium over its life span. (According to GE Healthcare, a manufacturer of the machines, that life span is 12.8 years.) In 2015 ...

  6. Energy density Extended Reference Table - Wikipedia

    en.wikipedia.org/wiki/Energy_density_Extended...

    Energy densities table Storage type Specific energy (MJ/kg) Energy density (MJ/L) Peak recovery efficiency % Practical recovery efficiency % Arbitrary Antimatter ...

  7. Prices of chemical elements - Wikipedia

    en.wikipedia.org/wiki/Prices_of_chemical_elements

    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.

  8. Explainer-What is helium and why is it used in rockets? - AOL

    www.aol.com/news/explainer-helium-why-used...

    Helium also has a very low boiling point (-268.9°C or -452°F), allowing it to remain a gas even in super-cold environments, an important feature because many rocket fuels are stored in that ...

  9. Helium - Wikipedia

    en.wikipedia.org/wiki/Helium

    There are two liquid phases: Helium I is a conventional liquid, and Helium II, which occurs at a lower temperature, is a superfluid. Helium I Below its boiling point of 4.22 K (−268.93 °C; −452.07 °F) and above the lambda point of 2.1768 K (−270.9732 °C; −455.7518 °F), the isotope helium-4 exists in a normal colorless liquid state ...