98.2 percent pure helium. However, with activated charchol, it produces 99.995 percent pure helium. Helium, with the symbol He, has an atomic number of 2, and an atomic mass of 2 AMU's. It has no color. Helium gas is unreactive, colorless, and odorless. Helium has an extremely low melting point (-452 F), and boiling point of close to absolute zero. Helium cannot be solidified by lowering temperature, but can be by increasing pressure to 25 atmospheres. This allows for helium to be used as a coolant in many low-pressure devices, such as rocket engines. It is used to cool liquid hydrogen fuel in these engines. Due to helium's ability to function at extremely low temperatures, helium is the ideal substance to use for cryogenic research. When properly cooled, the temperature of helium can go down to a few Micro-Kelvin's. Originally for balloons and blimps (airships), hydrogen was the primary substance used. Hydrogen, with an atomic mass of 1, is the lightest atom, and hence will give you the best performance for airships. However, because hydrogen only has 1 electron in its outermost energy level, it is unstable, and tends to spontaneously combust when mixed with oxygen. One of the most obvious demonstrations of this was the crash of the German airship, the Hindenburg (below left) in 1937 As you can see, the results were not pretty. In more modern times, Helium is used because it is a stable element (below right). Because of it's affordable price, and wide array of properties and uses, helium is used all over the world. Everywhere from birthday parties to advanced cryogen research facilities, you are sure to see an application of it. One property that makes helium different than any other element, is its ability to reach extremely cold temperatures. Helium is the ideal substance to use for many different things, and luckily because of its great abundance in outer space, there will never be a shortage of helium. ...
