Everything About Helium: Understanding the Lightest Noble Gas and its Uses

Helium is one of the most fascinating elements in the periodic table. As a noble gas, it behaves differently from many other elements due to its exceptional stability and also serves various applications in our daily lives.

This article provides an understanding of Helium's physical and chemical properties and its uses. 

Table of Contents

• Must-Know Facts About Helium!
• What is Helium?
• Physical Properties of Helium
• Chemical Properties of Helium
• Uses of Helium

 Must-Know Facts About Helium!

Only after hydrogen is lighter. That’s why helium balloons float, they’re lighter than air! Unlike hydrogen, helium is completely non-flammable and doesn’t mix or react with other elements under normal conditions. Once helium is released into the air, it drifts into space. Since we extract it from natural gas pockets underground, it's not easy to replace.

What is Helium?

Helium is the second lightest and most abundant element in the universe after Hydrogen. It is identified by a colourless, odourless, tasteless, and completely non-toxic gas. Found in Group 18 of the periodic table of elements in chemistry, it's part of the noble gas family. 

The name "helium" comes from the Greek word helios, meaning sun, because it was first discovered not on Earth, but in the solar spectrum during a solar eclipse!

Interestingly, Helium is exciting and plays a fun part in daily lives, from inflating balloons to enabling space exploration.

Let's discuss its Isotopes, as Helium exists in nature mainly as two stable isotopes:

Isotopes of Helium

• Helium-3 (He-3);This is a rare isotope and has one neutron.
• Helium-4 (He-4); This is the most common isotope, making up over 99% of naturally occurring helium. It has two protons and two neutrons.

Though both are stable, Helium-4 is the isotope we encounter most often.

Also Read: 118 elements and their symbols and atomic number 

Physical Properties of Helium

Helium is unlike most other elements in several interesting ways:

Property	Description
State at Room Temperature	Gas
Colour and Smell	Colourless and odourless
Density	Much lighter than air
Boiling Point	Extremely low at –268.9°C (just a few degrees above absolute zero)
Solubility	Slightly soluble in water
Inert Nature	Chemically unreactive under normal conditions

It’s also the only element that doesn’t solidify under standard pressure, even at extremely low temperatures, making it vital in cryogenics.

Chemical Properties of Helium

Helium is known for being chemically inert, which means when exposed to air, it will not react easily that is:

• It doesn’t easily form compounds with other elements.
• It does not support combustion (a helium-filled balloon won’t catch fire like a hydrogen-filled one).
• Its valence shell is full with two electrons, making it highly stable.

In laboratory conditions, some helium compounds have been artificially created, but they are extremely rare and unstable.                                        

Uses of Helium in the Real World 

Helium Uses have various applications that are surprisingly serious and scientific:

• Helium is used as a coolant in MRI scanners and scientific devices because of its very low boiling point. Furthermore, in Medical Imaging, helium serves as a cooled superconducting magnet that is critical in MRI scanners.
• In welding, helium is used as a shielding gas in arc welding to avoid oxidation.
• The most curious aspect of Helium is that it performs best in Space Exploration, such as in pressurised fuel tanks in rockets.
• Helium in Leak Detection is utilised to sense tiny leaks in pipelines and high-vacuum systems.

Even though helium is found in abundance in the universe, it's relatively rare on Earth, and once released into the atmosphere, it escapes into space, making its conservation important.