What color light does radon produce?

The below article talks about the conditions under which the chemical element radon produces lights and some frequently asked questions about radon and its impacts on the world around us. 

What color light does radon give? 

Radon is a colorless, odorless, tasteless, and chemically non-reactive noble gas unless it is put under extreme conditions. Radon is the ONLY noble gas that does not produce light on reaction with electricity. However, it is theorized that solid radon would glow in a soft yellow light, which would turn orange-red as its temperature changes. 

Radon in a gas-discharge lamp

Experimenting with radon is almost impossible due to its short half-life, and since it has no stable isotope and is highly radioactive, it is rarely used in such experiments. However, it is theorized that radon would glow red in a gas-discharge lamp. Below is an illustration of how it might look:

Source: Images of elements, n.d. 

What are noble gases?

Noble gases make up Group 18 of the periodic table, and there are 6 of them that occur naturally, namely: Helium (He), Neon (Ne), Argon (Ar), Krypton (Kr), Xenon (Xe), and radioactive Radon (Rn). There were also previously known as inert gases or aerogens. Under normal or standard conditions, noble gases are tasteless, non-flammable, odorless, colorless, monoatomic, with really low chemical reactivity. They do not react unless they are subjected to extreme conditions and remain gaseous under normal circumstances. They stay liquid in a really short temperature range. 

They were initially called rare or inert gases because it was thought that these compounds were quite rare. However, research into the case found that these gases were quite common across the surface of the planet, and were not as rare as previously considered. In the case of being named inert gases, since they did not form any reactions under standard conditions, they were considered as chemically not active, and thus inert; this condition however has been proven false much later, when it was found that noble gases do react under extreme conditions. 

In the periodic table, every noble gas (Group 18 elements) is wedged between electronegative groups (Group 17- halogens) and electropositive groups (Group 1- alkali metals). Group 17 elements need to add electrons to achieve an octet and thus become negative ions, whereas Group 1 elements need to lose electrons to become positive ions. Noble gases are quite often used in various sectors, especially since they do not cause any reactions under standard conditions, and their total indifference to oxygen makes them a much-utilized option in terms of various activities. For example, helium and argon are often used for cutting, welding, metal refining processes, etc. Other uses of noble gases include the following:

  • Helium is used for filling buoyant balloons 
  • An oxygen-helium mixture can be used to treat asthma 
  • Argon provides an inert atmosphere that can be used in welding elements like titanium, aluminum, stainless steel, magnesium, etc.
  • Argon is also used in the production of titanium 
  • Small amounts of argon are used in germanium and silicon crystals used for electric light bulbs, transistors, etc. 
  • Helium is used to attain lower temperatures required for lasers. 
  • Helium is used in nuclear reactors as a cooling gas, used as a flow gas for liquid chromatography protocols, used in airships, etc. 
  • Xenon and krypton are used in the flash units of photographing equipment as it generates bright bouts of light. It has also been traditionally used in lighthouses. 
  • Neon, xenon, and krypton are used to produce different colored lights. 
  • Neon is used in sodium vapor lamps 
  • Krypton is used for miners’ helmets or caps
  • Radon is used for multiple research purposes

Frequently Asked Questions (FAQs): Can radon produce light? 

What color lights do the noble gases produce on reacting with electricity? 

Source: Lumen, n.d.

Neon gas produces strictly an orange-red light, other “neon” signs in different colors would not contain the neon gas. In a transparent glass tube, neon glows to a classic red. Each noble gas except for Radon glows a different color on reaction with electricity: Helium becomes pink, Krypton glows in a range of yellow: green, xenon gives a lavender blue shade, and argon produces a sky blue shade. Most neon signs today use argon in conjunction with other gases, because argon uses the least amount of energy to light up, and thus has lower power requirements in comparison to signs using other gases (De Lucchi L., 2017). 

What is a gas discharge tube, what is its purpose?

Gas Discharge Tubes (GDTs) are used to protect personnel and sensitive equipment from temporary bursts of hazardous voltages. These tubes divert extra current from the hot line to the ground line. They are usually used in places like power stations, industrial plants, inside office buildings, installed in a power transformer, or on the outer wall (Harris T. & Homer T., 2022). 


De Lucchi L. (2017, March 02). The science of Neon gas. sygns. Viewed on 02-06-2022. https://www.sygns.com/blogs/magazine/the-sa-ns-of-neon-gas 

Harris T. & Homer T. (2022, January 19). How surge protectors work. Howstuffworks. Viewed on 02-06-2022. https://electronics.howstuffworks.com/gadgets/home/surge-protector2.htm 

Images of Elements. (n.d.). 86 Rn Radon. Chemical Elements: A virtual museum. Viewed on 02-06-2022. https://images-of-elements.com/radon.php 

Lumen. (n.d.). The Noble Gases (Group 18). Viewed on 02-06-2022. https://courses.lumenlearning.com/introchem/chapter/the-noble-gases-group-18/ 

Pedersen T. (2018, August 01. Facts about Radon. Viewed on 02-06-2022. https://www.livescience.com/39546-radon.html 

Leave a Comment