Properties of Helium

Helium is a chemical element with the symbol He and atomic number 2. It is a colorless, odorless, tasteless, non-toxic, inert, monatomic gas that heads the noble gas group in the periodic table. Helium is the second lightest element and is the second most abundant element in the observable universe, being present at about 24% of the total elemental mass, which is more than 12 times the mass of all the heavier elements combined.

Occurrence

Helium is primarily obtained through the extraction from natural gas, where it is produced as a by-product of the natural decay of radioactive elements such as uranium and thorium.

Uses of Helium

• Balloon Inflation: Helium is commonly used to fill balloons due to its low density, which allows the balloons to float in the air.
• Cryogenics: Helium is used as a coolant in various applications, including in MRI machines and particle accelerators.
• Welding: Helium is often used as a shielding gas in arc welding processes.
• Diving: Helium is mixed with oxygen for deep-sea diving to prevent the onset of nitrogen narcosis.
• Aerospace Industry: Helium is used to pressurize and purge systems, as well as a fuel for rocket propulsion.

Isotopes of Helium

Helium has two stable isotopes, helium-3 and helium-4. Helium-4 is by far the most common, making up about 99.99986% of the helium on Earth. Helium-3 is present on Earth only in trace amounts but is believed to be more abundant on the moon.

Fun Facts about Helium

1. Helium is the only element that was discovered in space before it was found on Earth.
2. It has the lowest boiling point of all the elements, at -268.9 degrees Celsius.
3. Helium is the only element that cannot be solidified by lowering the temperature under standard atmospheric pressure.