ChemTalk

Noble Neon

The Element Neon

Introduction to Neon

The element neon, symbol Ne, is a noble gas that is colorless and odorless under standard conditions. In the presence of an electrical current, neon gas glows a familiar bright red-orange color. Neon is unreactive.

Ten Amazing Facts About Neon

  1. Neon has the narrowest liquid range of any element. The element exists in liquid form in a range of only 2.5℃.
  2. It is the second-lightest noble gas, with helium being the first.
  3. Even though it is fairly rare on Earth, neon is the fourth-most abundant element in the universe. It makes up 18 parts per million of air.
  4. The neon sign is the element’s most well-known application. The first one was made by Georges Claude in 1910 and was debuted at the Paris Expo. If you see a neon-sign that is not reddish-orange, the gas inside is not neon!
  5. Neon has about two-thirds the density of air. Therefore, a neon balloon would float, but it would rise slower than a helium balloon because helium is lighter.
  6. Breathing neon will make your voice a higher pitch, but not nearly as much as helium will.
  7. The name neon comes from the greek word “neos” meaning “new”
  8. Liquid neon is used as a cryogenic refrigerant, and it is also used to freeze corpses (creepy!).
  9. Helium and neon are the only elements that do not form compounds with other elements, although ions and ligands have been formed.
  10. Neon has 3 stable isotopes that occur naturally, and an additional 17 radioactive isotopes.

Neon in the Periodic Table

The element neon, with atomic symbol Ne, is a noble gas in group 18 on the periodic table. Like the other noble gases it has a full outer shell with 8 valence electrons and its electron configuration is [He]2s22p6. It is located in the p-block in the second period. Neon’s atomic number is 10.

Neon’s Cooling Capacity

In its liquid form, neon is used as a cryogenic refrigerant, meaning that it is a fluid that is used in the process of cooling objects below 150 K. Neon’s cooling capacity is very high. It has 40 times the cooling capacity (per volume) of liquid helium and over 3 times that of liquid hydrogen. Neon’s properties as a noble (and therefore inert) gas allow it to not react or mix with other elements. These properties, as well as its very low boiling point, make it effective for use as a refrigerant.

Rarity of Neon

In both liquid and gaseous forms, neon is very rare and thus expensive on Earth. It is very light, has a high vapor pressure at low temperatures, and is nonreactive. These properties prevent neon from being trapped in the formation of Earth from clouds of dust. Neon makes up 0.00182% of Earth’s atmosphere. By contrast, neon is the fourth most abundant element in the universe.

Neon’s Applications in Today’s World

What is neon used for?

In addition to its use as a cryogenic refrigerant, neon is mostly used in different light sources, including signs and lasers.

Neon Lights and Signs

Perhaps the most famous application of neon, the signature red-orange neon lights were invented in 1910. Glass tubes containing neon atoms draw out different shapes and letters. Passing an electric current through the tube excites the outer-shell electrons, causing them to jump up one energy level. When the atoms eventually fall back down to their original energy level, they release energy in the form of red-orange light.

Helium-Neon Lasers

In a similar mechanism to neon signs, electric currents excite helium and neon atoms in discharge tubes. The collisions between the atoms transfer and release energy. This amplifies the lights inside the tube and produces the laser. The He-Ne lasers emit bright red lights with wavelengths of 632.8 nanometers (nm).

History of Neon

When and how was neon discovered?

British chemists William Ramsay and Morris Travers discovered the element neon in 1898. In his experiment, Ramsay boiled a sample of liquid air and captured the gases as they evaporated, a process called fractional distillation. After identifying and ruling out nitrogen, oxygen, and argon, Ramsay discovered krypton. Later, he discovered another gas that emitted a red-orange light under spectroscopic discharge. This element turned out to be neon. It was named after the Greek word neos, meaning “new.”

Neon Reactions

Because it is a noble gas, neon is stable with a complete octet of electrons. Neon is an inert gas that does not react with any other elements.

Neon Compounds

The element is not reactive, but there are a few exceptions, such as a few molecular ions and excimers. Excimers (short for “excited dimer”) are short-lived dimeric molecules. One of the atoms in excimers must have a complete octet of electrons. Some examples include Van der Waals molecules (ex: LiNe), ligands (ex: Cr(CO)5Ne), and ions (ex: NeH+). Both Van der Waals molecules and ligands have relatively weak bonds.

Isolation of Neon

In the same way chemist William Ramsay discovered the element, scientists can isolate neon. Because of the element’s extremely low boiling point, bringing liquid air into contact with activated charcoal absorbs the neon and hydrogen from the liquid air. Then, adding oxygen to the activated charcoal and its absorbed gases turns the hydrogen into water, isolating the neon element.

Neon Oxidation States

Because it is a noble gas, neon’s oxidation state is zero.

Physical Properties of Neon

  • Symbol: Ne
  • Melting point: -248.6oC
  • Boiling point: -246oC
  • Density: 0.000825 g/cm3 
  • Atomic weight: 63.55u
  • Atomic number: 29
  • Electronegativity: n/a
  • Classification: noble gas
  • Natural abundance of neon in the earth’s crust: 3*10-7%
  • Electron shell configuration: [He]2s22p6
  • Isotopes: neon-20, neon-21, neon-22
  • Found naturally in the minerals: none
  • Toxicity: nontoxic

Where Can I Buy Neon?

You can buy neon online.