Hi Good Evening Everybody, Win a Brand N


Hi Good Evening Everybody,

Win a Brand New Samsung Galaxy Tab 3 Participating in World of chemicals 2014 International Essay Competition ” The topic for Essay Competition 2014 – “Reducing harmful chemical footprint, a reality?
Last Date to Submit is 15-5-2014
Below Link will give you detailed info on topic and were to submit your essay
http://www.worldofchemicals.com/earthdayessaycompetition
http://ow.ly/i/5mS3x

chemical properties – Helium symbol, electronic configuration, density


Helium
Description:

Helium is a monatomic gas that heads the noble gas group in the periodic table. Its boiling and melting points are the lowest among the elements and it exists only as a gas except in extreme conditions. It is the second most abundant element in the universe. It is used in cryogenics, particularly the cooling of superconducting magnets, with the main commercial application in MRI scanners. Helium’s other industrial uses as a pressurizing and purge gas, and a protective atmosphere for arc welding and processes such as growing crystals to make silicon wafers, account for half of its use. Economically minor uses, such as lifting gas in balloons and airships are popularly known. As with any gas with differing density from air, inhaling a small volume of helium temporarily changes the timbre and quality of the human voice. In scientific research, the behavior of two fluid phases of helium-4, helium I and helium II, is important to researchers studying quantum mechanics and to those looking at the effects that temperatures near absolute zero have on matter.
Chemical Properties.
Appearance Colorless Gas
Atomic Number 2
Atomic Weight 4.0026 g/mol
Block s
Boiling Point −268.9 °C
CAS Number 7440-59-7
Class 2.2
Crystal Structure Hexagonal Close-Packed
Density 0.1786 g/l
EINECS Number 231-168-5
Electron Configuration 1s2
Group 18
Ionization Energy 2372.3 kJ/mol
Melting Point −272.2 °C
PG NA
Period 1
RTECS Number MH6520000
Symbol He

Helium manufacturers/suppliers – http://www.worldofchemicals.com/chemicals/manufacturers/fl/helium.html