liquid hydrogen
Quick Summary
Liquid hydrogen is hydrogen in its liquid state, achieved at extremely low temperatures. It has very low melting and boiling points, with a boiling point of -252.77 Ā°C. This state is utilized to achieve even lower liquefaction temperatures for hydrogen gas itself.12
Liquid hydrogen is a cryogenic propellant, meaning it must be stored at extremely low temperatures to remain in its liquid form. It is often used as a fuel in liquid-propellant rocket engines, typically paired with liquid oxygen as the oxidizer. While liquid hydrogen offers high exhaust velocities, its very low density can be a drawback.3
The production of hydrogen, which can then be liquefied, primarily involves processes like the catalytic steam-hydrocarbon process or partial oxidation of hydrocarbons. Hydrogen is a fundamental element with various applications, including in the chemical industry, as a rocket propellant, and in the synthesis of compounds like lithium hydride.456
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