What is Helium?

Helium, the second element on the periodic table, is a light and inert gas with unique properties. Known for its use in balloons and its presence in stars, Helium plays a vital role in science and the universe.

Atomic Number: 2

Symbol: He

Atomic Mass: 4.0026 u

Category: Noble Gas

State at Room Temperature: Gas

Discovered By: Pierre Janssen and Norman Lockyer (1868)

⚛️ Atomic Structure of Helium

Helium has a simple structure with two protons, two neutrons (in its most common isotope), and two electrons, making it stable and unreactive.

💡 Did you know? Helium-3, with one fewer neutron, is rare on Earth but abundant on the Moon and studied for potential use in fusion energy!

🔬 Helium Properties

Helium is the second most abundant element in the universe. It's colorless, odorless, and inert, with an extremely low boiling point, making it ideal for cryogenic applications.

🧬 How Was Helium Discovered?

In 1868, French astronomer Pierre Janssen and English astronomer Norman Lockyer detected Helium in the Sun's spectrum during a solar eclipse, before it was found on Earth.

⚡ Uses of Helium

💡 Fun Facts About Helium

⚠️ Safety & Precautions

Helium is non-toxic and safe, but inhaling it in large amounts can displace oxygen, leading to asphyxiation risks.

🔬 Explore More Elements