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  1. Helium - Wikipedia

    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 …

  2. Helium (He) - Periodic Table

    Helium (He) Helium is the 2nd element in the periodic table and has a symbol of He and atomic number of 2. It has an atomic weight of 4.00260 and a mass number of 4. Helium has two …

  3. Helium - Element information, properties and uses | Periodic Table

    Element Helium (He), Group 18, Atomic Number 2, s-block, Mass 4.003. Sources, facts, uses, scarcity (SRI), podcasts, alchemical symbols, videos and images.

  4. Helium | Definition, Properties, Uses, & Facts | Britannica

    Jun 6, 2025 · Ordinary air contains about 5 parts per million of helium, and Earth’s crust is only about 8 parts per billion. The nucleus of every helium atom contains two protons, but, as is the …

  5. Atomic Number of Helium He

    Atomic Number of Helium is 2. Chemical symbol for Helium is He. Number of protons in Helium is 2. Atomic weight of Helium is 4.002602 u or g/mol. Melting point of Helium is -272,2 °C and its …

  6. Helium - Atomic Number - He - Periodic Table of Elements

    Nov 21, 2020 · Helium is a chemical element with atomic number 2 which means there are 2 protons and 2 electrons in the atomic structure. The chemical symbol for Helium is He.

  7. Periodic Table of Elements: Los Alamos National Laboratory

    While helium normally has a 0 valence, it seems to have a weak tendency to combine with certain other elements. Means of preparing helium difluoride have been studied, and species such as …

  8. Helium (He) - Periodic Table

    Helium is a chemical element of the periodic table with chemical symbol He and atomic number 2 with an atomic weight of 4.0026 u and is classed as noble gas and is part of group 18 (noble …

  9. Helium - Periodic Table and Atomic Properties

    Helium is a chemical element with atomic number 2 which means there are 2 protons in its nucleus. Total number of protons in the nucleus is called the atomic number of the atom and is …

  10. Helium Facts - Atomic Number 2 or He - Science Notes and Projects

    May 18, 2015 · Helium is a chemical element with the symbol He and atomic number 2. It is a colorless, odorless, tasteless, non-toxic, inert, monatomic gas that heads the noble gas group …

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