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- 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 in the noble gas group in the periodic table
- 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 protons and two neutrons in its nucleus, and two electrons in one shell It is located in group eighteen, period one and block s of the periodic table
- 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
- Helium Facts - Atomic Number 2 or He - Science Notes and Projects
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 in the periodic table
- Helium | Definition, Properties, Uses, Facts | Britannica
Helium, chemical element, inert gas of Group 18 (noble gases) of the periodic table The second lightest element, helium is a colorless, odorless, and tasteless gas that becomes liquid at -268 9 degrees Celsius
- 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 the boiling point is -268,9 °C
- Periodic Table of Elements: Los Alamos National Laboratory
Seven isotopes of helium are known: Liquid helium (He-4) exists in two forms: He-4I and He-4II, with a sharp transition point at 2 174K He-4I (above this temperature) is a normal liquid, but He-4II (below it) is unlike any other known substance
- Helium | He (Element) - PubChem
Helium is a chemical element with symbol He and atomic number 2 Classified as a noble gas, Helium is a gas at 25°C (room temperature) 1s 2 B Cordero, V Gómez, A E Platero-Prats, M Revés, J Echeverría, E Cremades, F Barragán, S Alvarez, Dalton Trans 2008, 21, 2832-2838 DOI:10 1039 b801115j PMID:18478144 1 S 0
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