How Many Noble Gases are There in Periodic Table

Introduction

A periodic table is a group of organised elements where the chemical elements are arranged in a combination of rows and columns. It is called a chemistry icon and is widely used in physics, chemistry, and other life sciences. The periodic table states the properties of chemical elements that exhibit periodic dependence based on their atomic weights and atomic numbers, which itself is a graphic representation of the periodic law. The periodic table is divided into 4 rectangular sections called periodic blocks. The columns of a periodic table are called the group and the rows of a periodic table are called a period. The chemical elements from the same periodic table group exhibit similar chemical properties. In this article, we will be discussing the noble gases of the periodic table. The six naturally occurring noble gases are radioactive radon (Rn), xenon (Xe), krypton (Kr), argon (Ar), neon (Ne), and helium (He).

How Many Noble Gases are There in Periodic Table

Noble gases, also known as inert gases, are an important class of chemical elements with similar properties. They exhibit similar properties to other elements in the periodic table under standard conditions like odourless, colourless, and monatomic gases with very less chemical reactivity. The known noble gases are neon (Ne), helium (He), krypton (Kr), argon (Ar), xenon (Xe), and the radioactive radon (Rn).

Noble gases are also produced synthetically in laboratories like Oganesson (Og), a synthetic product with very high radioactivity in the element. According to the IUPAC, this element has used the term "noble/inert gas" interchangeably with "group 18", because it is not too chemically noble and can be reactive, due to Newton’s relativistic effects. The half-life of the element Oganesson (Og) is extremely short, that is, 0.7 ms half-life.

In the first 6 periods of the periodic table, the noble/inert gases are the members of group 18. These noble gases are highly unreactive except when under specific extreme conditions. The inertness of noble gases is useful to create an inert atmosphere where reactants can react with themselves with more yield. For example, Argon (Ar) is used in incandescent lamps/ fluorescent bulbs to prevent the hot tungsten filament from oxidising. Another example is Helium (He) which is used in inhaling gas by deep-sea divers to prevent nitrogen, oxygen, and carbon dioxide toxicity.

The noble gas properties can be explained by modern theories of atomic structure: The outer shell of valence electrons of the noble gas elements is considered to be "full", which gives them very little tendency to participate in chemical reactions, and thus only a few hundred noble gas compounds exist till now. The boiling points and melting and for a given noble gas are too close together, which differs by less than 10 °C and hence they are liquids over only a very small temperature range.

Argon, neon, krypton, and xenon are present in the air, separated using an air separation column using the methods of liquefaction of gases and fractional distillation. Helium (He) is obtained from natural gas fields, having very high concentrations of Helium (He) in the natural gas, and separated using cryogenic gas separation methods. Radon (Rn) is a radioactive element, usually isolated from the radioactive decay of dissolved thorium, radium, or uranium compounds. These noble/inert gases have important applications in industries such as welding, lighting, chemical reactions and space exploration. The noble/inert gases show low chemical reactivity and so only a few hundred noble gas compounds have been formed. Some neutral compounds of helium and neon are involved in chemical bonds that have not been formed, while krypton, xenon, and argon show only minor reactivity.

Applications of The Noble Gases

• The noble/inert gases have low boiling and melting points and are thus useful as cryogenic refrigerants.

• A Helium (He) - Oxygen (O) breathing gas is used by sea divers at more than 55 m depths of seawater.

• Helium (He) is used as an inhaling gas to replace nitrogen, due to its low solubility in blood.

• Argon is useful in the synthesis of air-sensitive compounds (sensitive to nitrogen).

• Argon is mixed with nitrogen for filler gas in incandescent bulbs.

• Helium is used to ease the breathing of asthma sufferers.

• Xenon is used in the medical imaging of the lungs through hyperpolarized Magnetic resonance imaging (MRI).

• Radon is used in radiotherapy because of its high radioactivity and is only available in minute amounts.

• Oganesson is a synthetically designed noble gas chemical element which is too unstable and has no known application.

The colour of gas discharge emission of the noble gas elements depends on several factors, including the following:

• The discharge parameters of the noble gas elements like the electric field and current density, temperature, etc.;

• The gas purity of the noble gas elements which is even a small fraction of certain gases can affect colour;

• The material of the discharge tube envelope of the noble gas elements. The suppression of the Ultra Violet (UV) and blue components in the bottom row tubes are made of thick household glass.

Conclusion

There are currently six noble gas atoms present in history today and one synthetically processed noble gas element which has got a place in the periodic table. We discussed various properties of the noble gas elements in this article and it can be concluded that these noble gas elements play a very important role in our life, in the chemical industries, in balancing the ecosystem and in regulating the atmospheric concentrations of the other compounds present in the air. Argon, neon, krypton, and xenon are generally found in the air and are processed by liquefying and fractional distillation. Although noble gases are called rare gases, they are not uncommon on Earth or in the whole universe. In fact, Argon (Ar) is the third or fourth most abundant gas in the atmosphere, which is almost 1.3 per cent by mass, while krypton, neon, helium, and xenon are notably traced elements. Many people believe noble gases to be nonreactive and unable to form chemical compounds, but these elements don't form compounds readily and at high pressures, neon, helium, and argon can participate in chemical reactions.