[Chemistry Class Notes] on Helium Gas Formula Pdf for Exam

Helium is an element that is non-toxic and non-combustible. This element is symbolized as He which is also the Helium gas chemical formula. It has an atomic number 2. It is the first noble gas in the periodic table, that is, it is an inert gas. This monatomic gas is colourless, odourless, and tasteless. It was the very first gas that was detected in the sun and has varied uses in various fields. Helium is the second lightest and second most abundant element in the whole universe after hydrogen.

Helium Gas Molecular Formula

The molecular formula of helium gas is He. It mostly exists in a monatomic state. It has an electronic configuration 1s2. The structure of helium gas is a closed-packed crystal structure. Helium belongs to group 18, period 1. When exposed to the electric field, it displays a red-orange colour. 

The Helium Formula is not written as He2 as per the Molecular Orbital Theory. However, the Helium gas formula He2 holds true at times as in the liquid phase it has some Van Der-Waal force between them becomes dominant. Liquid helium does not solidify at normal pressure irrespective of the temperature.

Properties of Helium

The properties of Helium gas is as follows:

• The Molecular weight of Helium is 4.003 g/mol.

• The density of Helium is 0.1786 g/L. It is about one-seventh as dense as air.

• It is the lightest noble gas.

• It is chemically inert.

• It has a very low viscosity.

• Helium is a tasteless, odourless, and colourless gas.

• Helium chemical formula is He.

Helium, in general, due to its inert nature, does not form any chemical compounds in normal conditions but under special conditions of pressure and temperature, helium forms certain compounds like Helium oxide. The helium oxide formula can be written as HeO. It is often mashed with hydrogen to produce water and Helium gas or with carbon to produce carbon dioxide.

Helium is a very vital gas in the whole universe and finds numerous applications in several fields. It is essential for students to be well versed in its chemical properties.