Only a select group of scientists can show off the discovery of an element. The Scottish chemist William Ramsay is an extra special case within this illustrious company. He did not add a single element, but a whole group to the periodic system: the noble gases. That earned him a Nobel Prize in 1904. He tracked down the noble gases when he discovered the colorless, odorless and hardly any reactive argon in 1894.
Argon is the most common noble gas on earth, because it arises at the radioactive decay of potassium -40 in the earth’s crust and mantle. 1 percent of every breath consists of Argon. Yet the noble gas was only discovered at the end of the nineteenth century. Although the Brit Henry Cavendish saw the first instructions in 1785.
Cavendish investigated the composition of air. He noted that if he had removed all the well -known gases from an air sample, a small bell unknown gas was left. He could not find out what this enigmatic leftover consisted.
More than a century later, Ramsay and the British Lord Rayleigh plunged into a similar issue. Rayleigh had discovered that nitrogen from the atmosphere had a higher density than when he removed nitrogen from a chemical connection. He suspected that the atmospheric nitrogen still contains a gas. Together with Ramsay, he managed to insulate this mysterious gas in 1894 by repeatedly blowing atmospheric nitrogen gas over glowing hot magnesium, so that the nitrogen binds to magnesium and destroys as a magnesium nitride.
In their publication (from 1895), Ramsay and Rayleigh describe how they have tried with all their might to have the new discovered gas enter into a chemical reaction with a laundry list of fabrics. From oxygen and hydrogen to red -hot phosphorus and potassium nitrate; Nowhere did the gas respond to or with it. That is why the two presented the name Argon, after the Greek word for inactive or lazy (Argos).
Barely a year later, Ramsey discovered that helium gas hardly responds with other substances. That motivated him to add a noble gas group to the periodic system of Mendelejev. He soon expanded that group with Neon, Krypton, Xenon and later Radon. For a while some chemists thought that these noble gases do not enter into chemical reactions at all. Until in the 1960s it was possible to have noble gases form some chemical compounds. Argon held up for longer. The first Argon connection (Argonfluorohydride) was only established in 2000 -and only at -265 ° C and under the influence of UV radiation.
For a gas that is chemically ‘lazy’, Argon has a surprising number of applications. Double glass insulates even better if you fill the space in between with Argon, because it leads poorly heat. That is why it is sometimes used to inflate diving suits. You can protect old documents against oxidation by storing them closed in the non-reactive argon gas. And in light bulbs filled with Argon, the filament does not burn.
Just like Neon, Argon transmits clear light when you hunt an electric current: pure argon colors purple, with mercury it is blue. Blue-green Argon lasers are used in ophthalmology and for cancer therapy. The ‘lazy’ noble gas is therefore put to work.