Not So Elite After All
"Heavier-than-air flying machines are impossible." -- Lord Kelvin, President, Royal Society, 1895. This quote soon came back to haunt the good scientist less than ten years later when the Wright brothers made their first flight on the beach at Kitty Hawk, North Carolina. Rash statements about what can and cannot be done have permeated both the scientific literature and the popular press for decades. Then somebody goes out and does what “couldn’t be done”.
Amazing But True
- Doubts about “flying machines” were not dispelled after the historic flights of the Wright brothers. The editor of the London Times stated in 1905 “All attempts at artificial aviation are not only dangerous to life but doomed to failure from an engineering standpoint." Even Wilbur Wright had his doubts. In 1901, he said that he did not believe that humans would fly for another fifty years.
- The group 8 (or 18 in the new system) elements were long considered to be unreactive. A synonym for “noble gas” was “inert gas”. Generations of students were told that these elements did not react because they had a full outer shell of electrons. But there always has to be someone to push the limits.
- Several chemists in the early part of the twentieth century began to speculate about these gases. Study of the ionization potentials suggested that Xe might be a candidate for reactions under the appropriate conditions. After several failed attempts over the years, success was achieved in 1962 with the synthesis of XeF4. Other xenon compounds soon followed, as well as some krypton compounds. Argon followed close behind with a fluorohydride derivative. More recently, a compound containing xenon and gold has been produced. So far, the other noble gases have resisted reaction.
Xenon headlamps are a popular feature on modern cars. However, they are actually metal-halide lamps that contain xenon gas. The effect of the gas is to allow the lights to produce adequate light very quickly
- Watch a video about xenon chemistry at the link below:
Show What You Know
Use the links below to learn more about noble gases, then answer the following questions.
- What is xenon used for?
- What did Bartlett believe that PtF6 could do with noble gases?
- Does neon form compounds?
- What compounds does argon form?