Atomic Number of Helium

Helium Atomic Number

Atomic Number of Helium is 2.

Chemical symbol for Helium is He. Number of protons in Helium is 2. Atomic weight of Helium is 4.002602 u or g/mol. Melting point of Helium is -272,2 °C and its the boiling point is -268,9 °C.

» Boiling Point » Melting Point » Abundant » State at STP » Discovery Year

About Helium

The name of this element takes source from the Greek word meaning the Sun, primarily because it was discovered by astronomers to be present in the Sun prior to its being detected on our planet. Known as the second most common element in the Universe (though it is quite rare on our planet), Helium is one of the Noble gases, which is not reactive and does not mix with other elements to create other chemical compounds. The boiling point of Helium is the lowest of the ones in all other elements in the Periodic Table. Helium is lighter than air and is used in balloons, airships, and similar kind of devices. It is also a very effective cooling agent which is used in medicine and industry. As a mixture with neon, helium is used in common scanning devices in modern technology.

Uses of Helium

Helium which is the second lightest element after hydrogen is used to make airships such as blimps and weather balloons float in the air. It is also useful in scuba diving to prevent divers from getting too much oxygen. So divers use a mixture of helium and oxygen. Besides, you can see that helium is used in meteorology, in hard disk drives, and in rocket propulsion. Because helium is the coldest in liquid form, it is mostly used as a coolant in cryogenics too. There is also another use of helium as a carrier gas for gas chromatography.

Compounds with Helium

Properties of Helium Element

Atomic Number (Z)2
Atomic SymbolHe
Atomic Weight4.002602 u
Density0.0001785 g/cm3
Melting Point (K)unknown
Melting Point (℃)-272,2 °C
Boiling Point (K)4.22 K
Boiling Point (℃)-268,9 °C
Heat Capacity5.193 J/g · K
Abundance0.008 mg/kg
State at STPGas
DescriptionNoble gas
Electronegativity (Pauling) χno data
Ionization Energy (eV)24.58741
Atomic Radius31pm
Covalent Radius32pm
Van der Waals Radius140
Valence Electrons2
Year of Discovery1895
DiscovererRamsay and Cleve

What is the Boiling Point of Helium?

Helium boiling point is -268,9 °C. Boiling point of Helium in Kelvin is 4.22 K.

What is the Melting Point of Helium?

Helium melting point is -272,2 °C. Melting point of Helium in Kelvin is unknown.

How Abundant is Helium?

Abundant value of Helium is 0.008 mg/kg.

What is the State of Helium at Standard Temperature and Pressure (STP)?

State of Helium is Gas at standard temperature and pressure at 0℃ and one atmosphere pressure.

When was Helium Discovered?

Helium was discovered in 1895.