Liquid helium

Liquid helium cooled below the Lambda point, where it exhibits properties of superfluidity

At standard pressure, the chemical element helium exists in a liquid form only at the extremely low temperature of −269 °C (about 4 K or −452.2 °F). Its boiling point and critical point depend on which isotope of helium is present: the common isotope helium-4 or the rare isotope helium-3. These are the only two stable isotopes of helium. See the table below for the values of these physical quantities. The density of liquid helium-4 at its boiling point and a pressure of one atmosphere (101.3 kilopascals) is about 0.125 grams per cm3, or about 1/8th the density of liquid water. [1]

Liquefaction

Helium was first liquefied on July 10, 1908, by the Dutch physicist Heike Kamerlingh Onnes at the University of Leiden in the Netherlands. [2] At that time, helium-3 was unknown because the mass spectrometer had not yet been invented. In more recent decades, liquid helium has been used as a cryogenic refrigerant, and liquid helium is produced commercially for use in superconducting magnets such as those used in magnetic resonance imaging (MRI), nuclear magnetic resonance (NMR), Magnetoencephalography (MEG), and experiments in physics, such as low temperature Mössbauer spectroscopy.

Other Languages
العربية: هيليوم سائل
català: Heli líquid
čeština: Kapalné helium
español: Helio líquido
فارسی: هلیم مایع
français: Hélium liquide
한국어: 액체 헬륨
Bahasa Melayu: Helium cecair
polski: Ciekły hel
português: Hélio líquido
русский: Жидкий гелий
slovenščina: Kapljevinski helij
Türkçe: Sıvı helyum
Tiếng Việt: Heli lỏng
粵語: 液化氦
中文: 液氦