Helium (He) – Periodic Table [Element Information & More]

Helium element (He) is in group 18 and period 1 of a periodic table. Helium is in the p-block and it is classified as a noble gas on the periodic table.

There is a lot more information related to helium which is mentioned in the Information Table given below.

So let’s dive right into it!

Table of contents

• Helium element (Information Table)
• Helium element in Periodic table
• Facts about Helium
• Properties of Helium
• Uses of Helium

Helium Element (Information Table)

The important data related to helium element is given in the table below.

Appearance of helium	Colorless gas
Atomic number of helium	2
Symbol of helium	He
Atomic mass of helium	4.002 u
Protons, Neutrons & Electrons in helium	Protons: 2, Neutrons: 2, Electrons: 2
State of helium (at STP)	Gas
Group number of helium in periodic table	18
Period number of helium in periodic table	1
Block of helium in periodic table	p-block
Category of helium	Noble gases
Bohr model or Electrons per shell or Electrons arrangement in helium	2 electrons in 1st shell
Electron configuration of helium	1s2
Orbital diagram of helium
Valence electrons in helium	2
Atomic radius of helium (van der Waals radius)	140 picometers
Density of helium	0.1786 g/L
1st ionization energy of helium	24.587 eV
Main isotope of helium	4He
Melting point of helium	0.95 K or -272.2 °C or -457.9 °F (at 2.5 MPa)
Boiling point of helium	4.22 K or -268.9 °C or -452 °F
Crystal structure of helium	Hexagonal closed packing (HCP)
Discovery of helium	By Pierre Jules César Janssen, and Sir Joseph Norman Lockyer (in 1868)

Also see: Interactive Periodic Table (It has rotating bohr models as well as many other details of all the 118 elements in a single periodic table).

Helium element in Periodic table

The Helium element (He) has the atomic number 2 and is located in group 18 and period 1. Helium is a nonmetal and it is classified as a noble gas element.

Facts about helium

Here are a few interesting facts about helium element.

1. Helium is a very light gas and so it escapes the earth’s atmosphere.
2. Helium shows the properties of superfluid at absolute zero temperature.
3. Helium is the second most abundant element found in the universe which is around 24%. (Hydrogen is the most abundant element which is around 74%).
4. Out of all the 118 elements on the periodic table, the helium atom has the smallest atomic size.
5. Helium was first discovered in the atmosphere of the Sun.
6. On the earth, the helium gas can be obtained by radioactive decay of thorium and uranium.

Properties of helium

Here is a list of some physical properties and chemical properties of helium.

Physical properties of helium

• Helium is a colorless, odorless and tasteless gas.
• Helium is an element that has the smallest atomic size out of all the 118 known elements.
• Helium is lighter than air and so it easily escapes the earth’s atmosphere.

Chemical properties of helium

• Helium is chemically inert and so it does not show much chemical reactivity at normal conditions. However, helium can form unstable compounds with tungsten, iodine, sulfur, fluorine and phosphorus under extreme conditions.
• Helium is considered to be the 2^nd least reactive element after neon.

Uses of helium

Here are some uses of the helium element.

• Mostly helium is used in cryogenic applications for cooling the superconducting magnets.
• As helium is chemically inert, it is used as a shielding gas in Gas Tungsten Arc Welding.
• Helium is also used in leak detection in industries.
• Helium is lighter than air, so it is also used in airships and balloons.
• Helium can be used as a carrier gas for gas chromatography.

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