Noble Gases

Neon, argon, krypton, and xenon are known as Noble Gas. Those gasses are found in the air and are obtained by liquefying them. Primarily helium is formed from the cryogenic separation of natural gas. Radon is a radioactive Noble Gas. It is produced from the radioactive decay of heavier elements like radium, thorium, and uranium. 118 Elements in the periodic table are manufactured radioactive elements. This radioactive element is produced by striking a target with accelerated particles. Scientists may find some extraterrestrial sources of Noble Gasses shortly. Helium can be more actively found on more giant planets than on Earth.

Introduction to Physical and Chemical Properties of Noble Gasses

In the modern periodic table, group 18 belongs to Noble Gasses. This group consists of a Chemical series of gasses including Argon, helium, neon, krypton, xenon, and radon. Radon is the only radioactive out of all. As the elements of the group hold the maximum number of electrons in their outermost shell, they are considered as the most stable elements of the periodic table. As they are already stable, they react very rarely with the other elements. Noble Gasses are also known as inert and rare gasses. Group 18 was characterized later on as compared to other groups of elements. 

During Mendeleev's time, Noble Gasses were not discovered. In the late 18th century, Henry Cavendish was the first person to discover Noble Gasses which were given the place of zero groups and were renamed as group 18 in the periodic table by the IUPAC convention.

Properties of Noble Gas

Those elements belonging to group 18 on the periodic table are Noble Gas. It is located in the column of elements on the right side of the periodic table.

There are seven Noble Gas elements in the periodic table: helium, neon, argon, krypton, xenon, and radon.

Noble Gasses are known as the least reactive Chemical elements. Noble Gasses are nearly inert because their atoms have an entire valence electron shell. So, they have a slight tendency to accept or donate electrons to form Chemical bonds.

Chemical Properties of Noble Gas

There are various Chemical Properties of inert gasses that are mentioned below:

1. Characteristics of Noble Gases are odorless, non-flammable, colorless, and monoatomic gas with low Chemical reactivity.

2. All the Noble Gasses conduct electricity and fluorescence which can be needed in many conditions to maintain a constant and safe environment.

3. All Noble Gasses are insoluble in water.

4. As they have a complete octet which makes them highly stable. So, they hardly react with other elements to form Chemical bonds because of their less tendency to either gain or lose electrons. But exceptions are everywhere. Xe is the exception in this case. Xenon is the Noble Gas that may form compounds either with fluoride or oxide.

Physical Properties of Noble Gasses

Following are several Physical Properties of inert gasses:

1. Atomic Radii (Atomic size)

As we move down the group from helium to radon the atomic size of Noble Gasses keeps on increasing. This is because when going down the group, the number of occupied shells with valence electrons increases.

2. Boiling and Melting Points 

• At room temperature and pressure, all the elements of group 18 exist in a gaseous state.

• The melting and boiling point of all the Noble Gasses is very low due to the following reasons: 

• All consist of monatomic molecules that are held together by weak van der Waal forces of attraction.

• During melting and boiling of overall Noble Gasses, only a slight amount of heat is required to resist weak interatomic force.

• But, As we move down the group, the boiling and melting point of the Noble Gasses increases due to the following reason:

• When moving down in the group, the atomic radius increases which results in the formation of a strong Van Der Waals force of attraction between the atoms.

• As to overcome the interatomic force of attraction which becomes stronger, it also requires more energy during melting and boiling.

3. Density

All elements of group 18 have low densities. When going down the group, density increases as the atomic mass keeps on increasing.

4. Ionization Energy

In the periodic table, As we move down the group the first ionization energy keeps on decreasing. Noble Gasses have the highest ionization enthalpy from all the groups of the periodic table, reflecting that they are Chemically inert.

5. Ionization Potential

When going down the group, the atomic radii increase which increases the attractive force and ultimately results in the increase of polarity and decrease in the ionization potential. This is because the larger atom of the group in the valence electrons are held together less tightly by the atom as they are situated far away from the nucleus.

6. Electrical and Heat Conductivity

All Noble Gas except neon conducts electricity. All the inert gasses of group 18 are poor conductors of heat.

Spot of the Noble Gasses on the Periodic Table

The Noble Gasses are also known as inert gasses or rare gasses. They are located in Group VIII by the periodic table's International Union of Pure and Applied Chemistry (IUPAC). This column of elements is found on the far right side of the periodic table. This group is a subset of the nonmetals element. The elements are also known as the neon group or the helium group. The Noble Gasses ( with symbol ) are:

• Helium (He)

• Neon (Ne)

• Argon (Ar)

• Krypton (Kr)

• Xenon (Xe)

• Radon (Rn)

All of these elements are gasses at ordinary temperatures and pressure.  Radon consists only of radioactive isotopes.

Uses of the Noble Gasses

There are various practical uses of Noble Gasses, those are:

• The Noble Gasses are used for inert atmospheres, basically for arc welding.

• To protect specimens,

• To deter Chemical reactions.

• There are neon lamp

• Another use is krypton headlamps

• Also in lasers.

• Helium is used in balloons,

• Helium is used in deep-sea diving air tanks,

• Also to cool superconducting magnets.

Summary of Noble Gasses

• Noble gas is non-reactive. They do not react with any molecule or each other.

• At low pressure, Noble gas will conduct electricity and fluoresce.

• All the elements have complete electron distribution in the outer shell (oxidation number = 0)

•  All the element contains High ionization energies

• They have Very low electronegativities

• They have low boiling points (all monatomic gaseous at room temperature)

• No color, odor, or flavor under ordinary conditions (but may form coloured liquids and solids)

• Nonflammable

Note: Several properties of the Noble Gasses on the periodic table are positively correlated to the atomic size.The Following Table Shows Some Physical Properties of Inert Gas