There are eight known isotopes of helium. Helios is also the name of the Greek god of the Sun. Helium gets its name from the Greek word "helios" meaning "sun".
The element wasn't found on Earth until 1895. He noticed the new element when studying a solar eclipse. Helium was first discovered in 1868 by astronomer Pierre Janssen. Other applications include silicon wafers for electronics and as a protective gas for arc welding. The largest industrial user of helium gas is MRI scanners which use the gas to keep the superconducting magnets cool. It is not as light at hydrogen, but is a much safer gas as hydrogen is very flammable. Helium is used in balloons and airships to make them float. This conversion is called nuclear fusion. This creates the energy, heat, and light that powers the stars and the sun. Deep inside a star, intense pressures cause hydrogen atoms to convert into helium atoms. Helium is constantly being produced at the internal cores of stars. Helium from radioactive decay can be found trapped underground in natural gas reservoirs. However, new helium is created in the center of stars and also as part of radioactive decay on Earth. Scientists believe that most of the helium in the universe was created at the formation of the universe. There is very little in the Earth's atmosphere because it is so light that it eventually escapes into outer space. This makes it very unreactive and non-flammable. This means that its outside electron shell is filled with electrons. Helium is one of the inert or noble gases. Helium is the only element that does not solidify under ordinary pressures and remains a liquid even at absolute zero. It has very low boiling and melting points, meaning that it is generally found in the gas phase except under the most extreme of conditions. It is at the top of the noble gas group in the periodic table.Īt room temperature helium is an odorless, tasteless, colorless gas. Helium is the second lightest and second most common element in the universe.
Helium is also used to inflate the tires of large aircraft, weather balloons, and blimps because it is nonflammable. Helium is used for diluting the pure oxygen in deep-sea diving tanks because the helium has a low solubility in human blood.
Argon is used in arc welding and in common light bulbs, as it does not react with the metal at high temperatures. The noble gases are used in industry in arc welding, to dilute the oxygen in deep-sea divers' gas tanks, and to fill light bulbs. Krypton will form a solid with fluorine, and xenon will form a variety of compounds with oxygen and fluorine. The other noble gases will react on a limited scale under very specific conditions. Of the noble gases, only helium and neon are truly inert. In fact, the name of the element helium was derived from the Greek word Helios, used to refer to the sun. They are extremely rare in nature, and none was known until helium was discovered to exist on the sun. These gases were not discovered until the last five years of the 1800s. The elements in this group are helium, neon, argon, krypton, xenon, and radon. This means that they do not react with other elements because they already have the desired eight total s and p electrons in their outermost (highest) energy level. The group of elements at the far right of the table (Group 18) is known commonly as the noble gases. Let's look at the other side of the periodic table now.
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