Argon isotope dating Cam webfree
Cavendish was unhappy that so little was known about air.
He was particularly unhappy about the lack of information about the fraction of air (the majority) which was not oxygen.
He then added additional oxygen until all the nitrogen had reacted. Cavendish used aqueous sodium hydroxide to remove them from the apparatus.
[This would also, of course, have removed any carbon dioxide that was present.] He removed the remaining oxygen using potassium polysulfides. Cavendish wrote that this bubble “was not more than one hundred and twentieth of the bulk of the phlostigated air [nitrogen].” So, Cavendish is saying that air is at least 99.3 percent nitrogen/oxygen/carbon dioxide with a maximum 0.7 percent of something else.
We now know that the ‘something else’, argon, is very unreactive; this enabled Cavendish to find it, but it also prevented him finding out more about it.
If it could, he would know that air was entirely oxygen, carbon dioxide and nitrogen.
Cavendish used an electric spark in air to react the oxygen and nitrogen to form nitrogen oxides.
Eta Carinae has a mass of more than 100 Earth suns.William Ramsay discovered argon when he first saw its spectrum and realized it matched no other’s.Image: NASA, ESA, and the Hubble SM4 ERO Team Argon was the first noble gas to be discovered.The first hint of its existence came from English scientist Sir Henry Cavendish as far back as 1785.
The violet glow of ionized argon gas in a discharge tube.Image: Gianfuffo The percentage volume of each gas in earth’s dry atmosphere. Image: Mysid A faint line from argon shows in the spectrum of the doomed star Eta Carinae.