What is the uses of argon?

• Argon is widely used as an inert gas to create an oxygen- and nitrogen-free environment for various heat-treating processes.  
• It is used for metal production, welding and metallurgy, lighting and in the automotive industry. 
• Argon is used for filling fluorescent and incandescent light bulbs. Argon does not react with the filament and prevents oxygen from corroding it.  
• In the welding and metal fabrication industry, argon is used to create an inert atmosphere between the surrounding air and liquid metal. The gas also prevents oxidation risks and minimizes smoke emissions. 
• Argon is used in the automotive industry to weld mufflers, frames and other auto parts. It also creates a nitrogen- and oxygen-free environment for the annealing process and is an important component of airbags. The tires of some luxury vehicles contain argon to reduce road noise and protect the rubber.  
• In metal production, argon is used to create a non-reactive blanket during the manufacture of titanium and other reactive elements and as a protective environment for growing germanium and silicon crystals. 

Explain why the melting and boiling points of argon are higher than helium?

The atomic size of argon is bigger than helium. Thus, the forces of attraction between argon atoms are stronger than the forces of attraction between helium atoms. As a result, more heat energy is required to overcome the stronger forces of attraction between argon atoms. Hence, the melting and boiling points of argon are higher than helium.  

Why is helium gas used in airships while argon gas used in electric bulbs?

• Helium gas is suitable to fill airships because it is very light and non-flammable.
• Argon gas is suitable to use in electric bulbs because it is chemically inert. Hence, the hot tungsten filament in the electric bulb does not react with it. 

Uses of the noble gases

The noble gases are unreactive or inert, which makes them safe to use. They also glow when a current is passed through them at low pressure. These properties lead to many uses:

• Helium is used to fill balloons and airships, because it is much lighter than air – and will not catch fire.
• Argon is used to provide an inert atmosphere. For example it is used: as filler in tungsten light bulbs and to protect metals that are being welded.
• Neon is used in advertising signs. It glows red, but the colour can be changed by mixing it with other gases.
• Krypton is used in lasers – for example for eye surgery – and in car headlamps.
• Xenon gives a light like bright daylight, but with a blue tinge. It is used in lighthouse lamps, lights for hospital operating rooms, and car headlamps.

Why noble gases chemically inert?

Helium has a duplet electron arrangement whereas other noble gases have octet electron arrangements. These electrons arrangements are very stable. Hence, atoms of noble gases do not release electrons, accept electrons or share electrons with other atoms. Thus, they are chemically inert. 

Why is neon exists as a monoatomic gas?

• Neon is from the Noble Gases group on the periodic table. 
• Neon has electron arrangement is 2.8 (valence electron is 8). 
• Neon already achieves the octet electron arrangement. 
• Neon does not need to donate the electron with other element. 
• Therefore they do not gain or lose electrons making them exist as individual atoms. 
• Neon exists as a monoatomic gas. 

Why the boiling point of noble gases increases when going down the group?

The boiling point of noble gases increases when going down Group 18. This is because the atomic size of noble gases becomes bigger when going down Group 18. Thus, the forces of attraction between atoms become stronger when going down Group 18. More heat energy is required to overcome the forces between atoms. This causes the boiling point of noble gases to increases when going down Group 18.