Argon is denoted by the symbol Ar, and its atomic number is 18. It was discovered in 1894 by two Scottish scientists, Lord Rayleigh and Sir William Ramsay. It is considered as one of the noble gases, and it is located in group 18 of the Periodic Table. It is more common in the Earth's atmosphere than carbon dioxide. In fact, it is the third most common gas in the atmosphere (0.93%), and this makes it all the more surprising that scientists took so long to discover its presence.
In 1785, Henry Cavendish suspected the presence of argon, but could never discover it. This discovery occurred about a century later in 1894, when the two Scottish scientists performed an experiment, where they removed all the oxygen, nitrogen, carbon dioxide, and water, from a sample of air.
The reason for their hunch that another gas was present in the atmosphere stemmed from the conclusion that the pure nitrogen produced from chemical reactions, was lighter than the nitrogen obtained from the atmosphere. This implied a mixture of nitrogen along with some other mysterious gas. Argon was the first out of all the noble gases to be discovered, and until 1957, its symbol was simply A.
Like all other noble gases, argon is also a colorless, odorless, and monatomic gas, that has very low chemical reactivity. As a result of this, it does not react with most chemical elements and compounds, and maintains its stability. But unlike the other noble gases, it does form a few compounds like Argon Fluorohydride (HArF), a compound with hydrogen and fluorine.
Many people often wonder, Is argon an element or a compound?. The answer is that it is most certainly an element, and one look at the Periodic Table can confirm that. It is soluble in water, and dissolves at the same rate that oxygen does, and 2.5 times faster than nitrogen does. Even though it does not form any compounds at room temperature, it can form clathrates with water, if its atoms get trapped in some lattice of the water molecules. Some other ions of argon like ArH+ and ArF have also been observed by scientists.
The properties of this element make it a very useful indeed, and this can be seen in the wide range of common argon uses. Its low thermal conductivity and its inertness make it a very popular alternative for diatomic nitrogen as well. Other noble gases can be put to similar use, but this element is the preferred choice, due to its widespread presence in the atmosphere, and the ease with which it can be obtained as a byproduct during the production of liquid nitrogen and liquid oxygen.
- It is used in some high temperature industrial processes like graphite electric furnaces, due to its ability to stay stable at these high temperatures.
- It is used for metal inert gas welding, as well as in the production process of titanium, and other highly reactive elements.
- It is used as an asphyxiant for poultry, if a large number of the animals are to be culled in a humane way.
- Sometimes, it is also used to extinguish large fires, as it does not damage the containers and the equipment.
- It is also used as a preservative to increase the shelf life of certain food products, as it helps in displacing the oxygen and moisture present in the air.
- It is also used to store important National documents, like the Constitution and the Declaration of Independence, as its presence reduces gas leakage, and helps in anti-oxidation.
- Energy efficient windows make use of this element for thermal insulation as well.
- A dry scuba diving suit, is usually inflated with this gas, owing to its inertness.
- It has found some uses in the medical world as well.
It has properties that have proved to be very useful to the human race, and the ease and the economics of obtaining the element, mean that it can be put to a variety of different uses, unlike the other noble gases. Remember, that Argon in closed areas can be dangerous since it is an asphyxiant. So, one must avoid being in closed areas with this element. If it is handled and stored in the right manner, it can be very useful indeed, and this is highlighted by the number of areas where it has helped us.