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25 Οκτ 2024 · helium (He), chemical element, inert gas of Group 18 (noble gases) of the periodic table. The second lightest element (only hydrogen is lighter), helium is a colourless, odourless, and tasteless gas that becomes liquid at −268.9 °C (−452 °F). The boiling and freezing points of helium are lower than those of any other known substance.
Helium (from Greek: ἥλιος, romanized: helios, lit. 'sun') is a chemical element; it has symbol He and atomic number 2. It is a colorless, odorless, non-toxic, inert, monatomic gas and the first in the noble gas group in the periodic table.
After hydrogen, helium is the second most abundant element in the universe. It is present in all stars. It was, and is still being, formed from alpha-particle decay of radioactive elements in the Earth. Some of the helium formed escapes into the atmosphere, which contains about 5 parts per million by volume.
Definition. Helium is a colorless, odorless, and inert noble gas that is the second lightest and second most abundant element in the universe. It is a crucial element in various scientific and industrial applications, with its unique properties making it indispensable in fields ranging from cryogenics to medical imaging.
17 Σεπ 2024 · Helium – A noble gas with the chemical symbol He and atomic number 2, Helium is renowned for its inertness and lighter-than-air properties. It’s the second most abundant element in the universe, primarily formed through nuclear fusion in stars.
Helium is a chemical element. Its official symbol is He, and its atomic number is 2, which means it has two protons in its nucleus. Helium was named after Helios – the Greek Titan of the Sun – because it was first observed when analysing sunlight during a solar eclipse in 1868.
Helium is the second most abundant element in the universe. Only hydrogen occurs more often than helium. Helium is also the second simplest of the chemical elements. Its atoms consist of two protons, two neutrons, and two electrons. Only the hydrogen atom is simpler than a helium atom.
