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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 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 | 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
Learn the atomic number of Helium He Element properties of Helium; atomic symbol, weight, density, number of protons, electronegativity
- Helium - Atomic Number - He - Periodic Table of Elements
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
- 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) - 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 gases)
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