Noble Gases — Overview & Properties

What Are the Noble Gases?

They are elements in group (column) 8A of the periodic table. The elements that make up this group are helium ($He$), neon ($Ne$), argon ($Ar$), krypton ($Kr$), xenon ($Xe$), and radon ($Rn$). These elements have similar properties to each other and are different from other chemical elements.

Properties of Noble Gases

There are some properties that these elements share including:

• Mostly unreactive or inert because they have a full valence shell (outer shell), so they do not participate in much chemical bonding. They obey the octet rule.

• Krypton, xenon, and radon can be exceptions to the octet rule because of their d-orbitals. They mostly form compounds with very electronegative elements, like fluorine and oxygen.

• Radon has the most metallic character and can form ionic bonds with fluorine. Radon's most common oxidation state is a +2 charge.

• Colorless

• Odorless

• Gaseous state. They have very low boiling and melting points.

• Do not accept or donate electrons easily.

• Emit different colors of light in an electric current.

Fun Facts about the Physical Properties of Noble Gases

Helium is found in low amounts on Earth in the air. Because it is a gas, it is not found in many other sources. The same is true for many other noble gases. However, in the whole universe, $He$ is the second most abundant element. $He$ is often used to fill balloons because it is lighter than air. $He$ is used by scientists in its liquid form to keep reactions and instruments at a cold, low temperature.

Neon has been used in neon signs for many years. When $Ne$ gas is in a glass tube and an electrical field is added, the gas emits a red-orange light. Other noble gases are used in neon sings, but the color of neon distinguishes it from other gases.

Argon makes up about 1% of the Earth's atmosphere. Since $Ar$ is inert it is can be used to replace the atmosphere of instruments and scientific equipment. Using $Ar$ instead of air is useful when working with chemicals and compounds that are air sensitive or react with air.

Krypton can sometimes react with fluorine to create compounds. One such compound is used for lasers. $Kr$ can also be used in photography.

Xenon can create some compounds, for example with fluorine. $Xe$ like other noble gases is used in signs an photography. It has also been used anesthesia, but is expensive and not frequently used.

Radon is the only noble gas that is radioactive. There have been some studies linking radon to cancer, and it is harmful if inhaled.

(Video) Noble Gases - The Gases In Group 18 | Properties of Matter | Chemistry | FuseSchool

by FuseSchool - Global Education

In this video, you will learn about properties of noble gases (the group $18$ elements). They have 8 valence electrons. Once called inert gases, these elements are colorless and exist as single atoms. They have many uses today, such as being used in headlights, light bulbs, and in the medical field.