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  1. Imágenes

    • Definition of Atomic Number | with Examples
    • Diagram representation of the element helium Vector Image
    • First 20 Elements of the Periodic Table
    • Atomic mass of helium - noredbonus

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  2. www.rsc.org › periodic-table › elementHelium - Element information, properties and uses | Periodic...

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

    • Videos of Helium

      Donald Duck voices and floating balloons. Helium is element...

    • History

      The Royal Society of Chemistry brings you the history of the...

    • Help

      The number of atoms of the element per 1 million atoms of...

    • Manage My Membership

      Registered charity number: 207890 Skip to main content. Top...

    • Gadolinium

      Atomic number The number of protons in an atom. Electron...

    • Polonium

      Uranium ores contain minute traces of polonium at levels of...

  3. en.wikipedia.org › wiki › HeliumHelium - 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, tasteless, non-toxic, inert, monatomic gas and the first in the noble gas group in the periodic table.

  4. www.britannica.com › science › helium-chemical-elementHelium | Definition, Properties, Uses, & Facts | Britannica

    Helium is a colourless, odourless, and tasteless gas that becomes liquid at −268.9 °C. It has two stable isotopes, helium-3 and helium-4, with different physical and chemical properties.

  5. periodictable.chemicalaid.com › element › HeHelium (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 protons and two neutrons in its nucleus, and two electrons in one shell.

  6. www.periodic-table.org › Helium-atomic-numberHelium - Atomic Number - He - Periodic Table of Elements

    21 de nov. de 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. It is a colorless, odorless, tasteless, non-toxic, inert, monatomic gas, the first in the noble gas group in the periodic table.

  7. periodic-table.com › heliumHelium Element | History, Uses, Facts, Physical & Chemical...

    Definition, mass & chemical names. Helium is the second most abundant element in the universe and is primarily produced because of radioactive decay. It was discovered in 1868 by Jules Janssen and Norman Lockyer. History and Discovery. The discovery of helium is linked with its primary sources, the sun.

  8. sciencenotes.org › helium-factsHelium Facts - Atomic Number 2 or He - Science Notes and Projects

    18 de may. de 2015 · Learn about helium, the second element of the periodic table, with atomic number 2 and symbol He. Find out its discovery, name origin, isotopes, physical and chemical properties, and more.