companydirectorylist.com  Global Business Directories and Company Directories
Search Business,Company,Industry :


Country Lists
USA Company Directories
Canada Business Lists
Australia Business Directories
France Company Lists
Italy Company Lists
Spain Company Directories
Switzerland Business Lists
Austria Company Directories
Belgium Business Directories
Hong Kong Company Lists
China Business Lists
Taiwan Company Lists
United Arab Emirates Company Directories


Industry Catalogs
USA Industry Directories














  • 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
  • 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 constitutes about 23 percent of the mass of the universe and is thus second in abundance to hydrogen in the cosmos Helium is concentrated in stars, where it is synthesized from hydrogen by nuclear fusion
  • Atomic Number of Helium He
    Learn the atomic number of Helium He Element properties of Helium; atomic symbol, weight, density, number of protons, electronegativity
  • 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 – 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 It is a colorless, odorless, tasteless, non-toxic, inert, monatomic gas, the first in the noble gas group in the periodic table
  • Helium - Periodic Table and Atomic Properties - Material Properties
    Atomic Number – Protons, Electrons and Neutrons in Helium 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 given the symbol Z




Business Directories,Company Directories
Business Directories,Company Directories copyright ©2005-2012 
disclaimer