What is the Second Most Abundant Gas on Earth?

The second most abundant gas on Earth, by volume, is Helium (He). While nitrogen reigns supreme, composing approximately 78% of our atmosphere, helium represents the second largest component in terms of overall abundance, although its location is far from our atmosphere.

The Abundance of Helium

While our atmosphere is dominated by nitrogen and oxygen, helium’s abundance lies primarily beneath the Earth’s surface. This is because helium is incredibly light and doesn’t readily bond with other elements, leading to its escape from the atmosphere into space over geological time. However, large quantities are trapped in underground natural gas deposits.

How Helium is Formed

Helium is a unique element formed in two primary ways:

• Primordial Helium: This helium originated from the Big Bang and remains trapped within the Earth’s mantle and crust. It is released slowly over time.
• Radiogenic Helium: This helium is produced through the radioactive decay of heavy elements, such as uranium and thorium, in the Earth’s crust. Alpha particles emitted during this decay are, in fact, helium nuclei.

Where Helium is Found

The majority of commercially viable helium deposits are found associated with natural gas fields. This is because the helium, produced underground, becomes trapped alongside the hydrocarbons. Extraction plants separate the helium from the natural gas through a process called fractional distillation. Major helium-producing countries include the United States, Algeria, Qatar, and Russia. While present in smaller quantities in the atmosphere, extracting it directly from the air is prohibitively expensive.

Uses of Helium

Helium’s unique properties make it indispensable in a variety of applications.

Cryogenics

One of the most important uses of helium is in cryogenics. Its extremely low boiling point (-269°C or -452°F) makes it the ideal coolant for superconducting magnets used in MRI machines, particle accelerators (like the Large Hadron Collider), and other advanced technologies. Without helium, many of these technologies would simply not function.

Lifting Gas

Although hydrogen is lighter, helium is non-flammable and therefore much safer to use as a lifting gas in balloons and airships. While airships are not as prevalent as they once were, helium-filled balloons remain a common sight at events and in scientific research.

Leak Detection

Helium’s small atomic size allows it to permeate through tiny cracks and fissures. This property is exploited in leak detection for pressurized systems, such as pipelines, tanks, and even spacecraft.

Welding

Helium is used as a shielding gas in welding processes, particularly in arc welding. It protects the weld from atmospheric contamination, resulting in stronger and cleaner welds.

Other Applications

Helium also finds applications in:

• Deep-sea diving: Mixed with oxygen to create breathing gas.
• Semiconductor manufacturing: As a carrier gas.
• Scientific research: In various experiments requiring inert atmospheres.

FAQs About Helium

FAQ 1: Is Helium a Renewable Resource?

Helium is considered a non-renewable resource. Although it is constantly being produced through radioactive decay, the rate of formation is incredibly slow compared to the rate of consumption. Furthermore, once released into the atmosphere, it can escape into space.

FAQ 2: Why is there a Helium Shortage?

There have been concerns about a global helium shortage due to a combination of factors: limited sources, increasing demand, and geopolitical issues affecting supply chains. The shutdown of major helium production facilities and delays in the opening of new ones have also contributed to shortages and price increases.

FAQ 3: What are the Alternatives to Helium?

Finding viable alternatives to helium is challenging due to its unique properties. In some applications, hydrogen can be used as a lifting gas (with safety precautions). For cryogenics, alternative cooling methods are being explored, but none currently match the performance of liquid helium for certain applications.

FAQ 4: How is Helium Extracted from Natural Gas?

Helium is extracted from natural gas through a process called fractional distillation. The natural gas is cooled to extremely low temperatures, causing different components to condense into liquids at different points. Helium, with its extremely low boiling point, remains a gas and can be separated.

FAQ 5: What is the US Federal Helium Reserve?

The US Federal Helium Reserve, located in Amarillo, Texas, was a major source of helium for decades. It was established to ensure a stable supply for government agencies and private industry. However, legislation has mandated its sale and eventual closure.

FAQ 6: Is Helium Safe to Breathe?

Breathing pure helium is dangerous and can be fatal. It displaces oxygen in the lungs, leading to suffocation. While small amounts of helium can temporarily alter the sound of your voice, this is generally discouraged due to the potential risks.

FAQ 7: How Much Helium is Left in the World?

Estimating the exact amount of helium remaining in the world is difficult due to the vastness of underground reserves. However, experts agree that current reserves are finite and that careful management and exploration for new sources are crucial.

FAQ 8: How Does Helium Affect Climate Change?

Helium itself does not directly contribute to climate change. It is an inert gas and does not trap heat in the atmosphere. However, the energy-intensive processes used to extract and transport helium can indirectly contribute to greenhouse gas emissions.

FAQ 9: Can We Synthesize Helium?

While technically possible to synthesize helium through nuclear reactions, the energy required and the complexity of the process make it completely impractical for commercial production. It is far more efficient to extract helium from natural gas deposits.

FAQ 10: What Happens if We Run Out of Helium?

Running out of helium would have significant consequences for various industries. Medical imaging, scientific research, and advanced technologies would be severely impacted. Finding alternative materials and developing more efficient helium recycling technologies are crucial.

FAQ 11: Are there Efforts to Recycle Helium?

Yes, there are increasing efforts to recycle helium, particularly in high-value applications like MRI machines and particle accelerators. Closed-loop systems are being developed to capture and reuse helium, reducing reliance on new sources.

FAQ 12: Why is Helium so Expensive?

Helium is relatively expensive due to a combination of factors: limited sources, complex extraction processes, high demand, and geopolitical influences on supply chains. Government policies and regulations also play a role in determining helium prices. The cost reflects the challenges in finding, extracting, and delivering this valuable resource.