# Monatomic Gases

## What are Monatomic Gases?

Monatomic is a combination of two words “mono” and “atomic” means a single atom. This term is used in both Physics and Chemistry and is applied to the gases as a monatomic gas. In the gaseous phase at sufficiently high temperatures, all the chemical elements are monatomic gases.

The noble gases are monatomic gases as they are unreactive in nature which is a property of these gases. They do find applications in daily life like:

• Helium is used in filling balloons as their density is lower than that of the air.
• Neon is used for creating advertising signs as they glow when electricity flows through it.
• Argon is used in a light bulb to prevent burning of the filament as it is unreactive in nature.

## What are Diatomic Molecules?

Diatomic molecules are those molecules that are composed of only two atoms. If a diatomic molecule is composed of the same element it is known as a homo nuclear and if it is composed of two different elements it is known as hetero nuclear.

## What is a Polyatomic Ion?

A polyatomic ion is also known as a molecular ion that is composed of two or more covalently bonded atoms. It is also referred to as a radical.

### Monatomic Examples

The noble gases are the examples of monatomic gases, and they are:

• Helium
• Neon
• Xenon
• Argon
• Krypton

### Diatomic Molecules Example

Diatomic elements are non-metals and exist in pure form as:

 Hydrogen H2 Nitrogen N2 Fluorine F2 Oxygen O2 Iodine I2 Chlorine Cl2 Bromine Br2

### Examples of Polyatomic Ions

Following are the common list of polyatomic ions:

 Anions Cations Chlorite $ClO_{2}^{-}$ Mercury $Hg_{2}^{2+}$ Nitrite $NO_{2}^{-}$ Ammonium $NH_{4}^{+}$ Peroxide $O_{2}^{2-}$ Hydronium H3O+ Bicarbonate $HCO_{3}^{-}$ Fluoronium H2F+ Bisulfate $HSO_{4}^{-}$ Phosphonium $PH_{4}^{+}$

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#### 1 Comment

1. Harshika

Excellent explanation 🧠