Helium | Helium Gas Definition, Properties, Uses & Facts

Helium | Helium Gas Definition, Properties, Uses & Facts

Helium: The Lighter-Than-Air Element Defying Gravity


Helium, the second most abundant element in the universe, is a fascinating and unique gas that has captivated scientists and enthusiasts alike for its extraordinary properties. In this blog, we'll delve into the definition, properties, uses, and interesting facts about helium.


Helium, denoted by the chemical symbol He, is a colorless, odorless, and tasteless noble gas. It holds the distinction of being the only element that remains liquid at absolute zero, making it an essential element to study in various scientific applications.

Helium  Chemical properties:

Chemical Symbol: He

Atomic Number: 2

Atomic Mass: The atomic mass of helium is approximately 4.0026 atomic mass units (u)

Helium Physical Properties:

1. State at Standard Temperature and Pressure (STP): At standard temperature (0 degrees Celsius or 32 degrees Fahrenheit) and pressure (1 atmosphere), helium exists as a colorless, odorless, and tasteless gas.

2. Density: Helium is the second lightest and least dense element, after hydrogen. Its low density contributes to its ability to make objects, like balloons, float in air.

3. Boiling Point: Helium has an extremely low boiling point of approximately -268.93 degrees Celsius (-452.07 degrees Fahrenheit), making it one of the few elements that remain liquid close to absolute zero.

4. Melting Point: Helium has a melting point of -272.2 degrees Celsius (-457.96 degrees Fahrenheit), which is only a few degrees above absolute zero.

5. Solubility: Helium is sparingly soluble in water and other common liquids, exhibiting very low solubility due to its inert nature.

6. Thermal Conductivity: Helium has the highest thermal conductivity of all gases. This property makes it useful in cryogenic applications, such as cooling superconducting magnets in medical MRI machines.

7. Molar Mass: The molar mass of helium is approximately 4.0026 grams per mole. It is significantly lighter than most other elements.

8. Atomic Radius: As a noble gas, helium has a small atomic radius. It has two electrons in its outer shell and is chemically inert, meaning it does not readily form compounds with other elements.

9. Miscibility: Helium is miscible with air, meaning it can evenly mix with the Earth's atmosphere. However, due to its lower density, helium tends to rise and disperse quickly.

10. Color: In its gaseous state, helium is colorless, contributing to its use in various applications without altering the appearance of gases it may be mixed with.

These physical properties, particularly its low density and inert nature, make helium valuable in a range of applications, from party balloons to critical scientific and industrial uses.

Helium Uses:

1. Balloons and Celebrations:

Helium's buoyant nature makes it the go-to gas for inflating balloons, creating an uplifting atmosphere at parties and events. Its non-flammable and safe properties make it an ideal choice for festive occasions.

2. Cryogenics and Superconductivity:

Helium is crucial in the field of cryogenics, where extremely low temperatures are required for scientific research and technology applications. It is used to cool superconducting magnets in devices like magnetic resonance imaging (MRI) machines and particle accelerators.

3. Welding and Leak Detection:

Helium is used in welding processes to shield molten metals from the surrounding air, preventing oxidation. Its small atomic size also makes it an effective tracer gas for leak detection in a variety of industries.

4. NASA and Space Exploration:

Helium has found its way into the realm of space exploration. It is employed to pressurize fuel tanks in rockets, ensuring a controlled release of propellants. Additionally, helium is used in satellite instruments and scientific balloons for atmospheric research.

Interesting Facts:

Helium was first discovered in 1868 by the French astronomer Pierre Janssen during a solar eclipse when he observed a new spectral line.

The United States established the National Helium Reserve in 1925, recognizing the strategic importance of helium for military and scientific purposes.

Helium is formed through the process of nuclear fusion in stars, primarily in the later stages of stellar evolution.


From floating balloons at celebrations to enabling cutting-edge scientific research, helium's unique properties and versatility have made it an indispensable element in various fields. As we continue to explore and utilize this extraordinary gas, its role in both everyday life and advanced technologies remains truly uplifting.

Also Read:

Hydrogen | Difference between Blue and Green Hydrogen | Hydrogen Fuel

Resolver (Electrical) | Rotary Electrical Transformer | What is the purpose of a resolver?

Full Authority Digital Engine Control (FADEC) System Description & Operation

Post a Comment