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Helium

physical science Maturity 11-13 Next article →

Helium is a very special gas found in our universe. It is a colorless and odorless gas that does not harm living things. Scientists call it an inert gas because it does not react easily with other things. It is the second-lightest element in the whole observable universe. After hydrogen, helium is the most common element found in space. It makes up about 24% of the total mass of elements. This is much more than all the heavier elements combined.

Helium atom QM
Helium atom QM

Most helium was made during the Big Bang a long time ago. Large amounts of new helium are also made inside stars. This happens through a process called nuclear fusion. In this process, stars join small parts together to make helium-4. This specific type of helium is the most common in space.

Binding energy curve - common isotopes
Binding energy curve - common isotopes

On Earth, helium is much harder to find. It is created when heavy elements like uranium break apart. This is called radioactive decay. This gas often gets trapped in natural gas fields deep underground.

Kansas Helium Marker
Kansas Helium Marker

Humans first discovered helium by looking at the Sun. In 1868, astronomers watched a total solar eclipse. During the eclipse, Jules Janssen saw a bright yellow line in the light. This line was a special signature in the solar spectrum. Later, Norman Lockyer saw the same yellow line from Britain. He believed this line came from a new element. He named it helium after the Greek word for the Sun.

Helium spectrum
Helium spectrum

Scientists later found helium here on Earth. In 1895, Sir William Ramsay isolated it from a mineral called cleveite. He used acid to separate the gas from the ore. At the same time, chemists in Sweden also found it. In 1908, Heike Kamerlingh Onnes did something amazing. He cooled the gas until it became a liquid. He could not make it a solid at normal pressure. It took more work and extra pressure to freeze it in 1926.

William Ramsay working
William Ramsay working

We use helium for many important jobs today. It is a great lifting gas for balloons and airships. Because it is so light, it makes them float. A huge part of helium is used for cooling. It cools superconducting magnets in MRI scanners at hospitals.

Modern 3T MRI
Modern 3T MRI

It is also used in welding and making silicon wafers. Helium is a non-renewable resource on our planet. Once it escapes into the air, it floats away into space. We must use it carefully because our supply is shrinking.

2 Helium
2 Helium
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🖼️ Images & Media (14)
File:Helium spectrum.jpg
Helium spectrum.jpg
File:William Ramsay working.jpg
William Ramsay working.jpg
File:Kansas Helium Marker.jpg
Kansas Helium Marker.jpg
File:Helium atom QM.svg
Helium atom QM.svg
File:Binding energy curve - common isotopes.svg
Binding energy curve - common isotopes.svg
File:HeTube.jpg
HeTube.jpg
File:Phase diagram of Helium-4-en.svg
Phase diagram of Helium-4-en.svg
File:2 Helium.png
2 Helium.png
File:helium-II-creep.svg
helium-II-creep.svg
File:Helium-hydride-cation-3D-SF.png
Helium-hydride-cation-3D-SF.png
File:Fluoroheliate-ion-3D-vdW.png
Fluoroheliate-ion-3D-vdW.png
File:Modern 3T MRI.JPG
Modern 3T MRI.JPG

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