In the laboratory it can be prepared by the electrolysis of water or by adding a manganese IV oxide catalyst to aqueous hydrogen peroxide. Help text not available for this section currently. Elements and Periodic Table History. This was oxygen although it was not identified as such. The credit for discovering oxygen is now shared by three chemists: an Englishman, a Swede, and a Frenchman. Joseph Priestley was the first to publish an account of oxygen, having made it in by focussing sunlight on to mercuric oxide HgO , and collecting the gas which came off.
He noted that a candle burned more brightly in it and that it made breathing easier. He had written an account of his discovery but it was not published until Atomic data. Bond enthalpies. Glossary Common oxidation states The oxidation state of an atom is a measure of the degree of oxidation of an atom.
Oxidation states and isotopes. Glossary Data for this section been provided by the British Geological Survey. Relative supply risk An integrated supply risk index from 1 very low risk to 10 very high risk. Recycling rate The percentage of a commodity which is recycled. Substitutability The availability of suitable substitutes for a given commodity. Reserve distribution The percentage of the world reserves located in the country with the largest reserves.
Political stability of top producer A percentile rank for the political stability of the top producing country, derived from World Bank governance indicators.
Political stability of top reserve holder A percentile rank for the political stability of the country with the largest reserves, derived from World Bank governance indicators. Supply risk. Young's modulus A measure of the stiffness of a substance.
Shear modulus A measure of how difficult it is to deform a material. Bulk modulus A measure of how difficult it is to compress a substance. Vapour pressure A measure of the propensity of a substance to evaporate. Pressure and temperature data — advanced. Listen to Oxygen Podcast Transcript :. You're listening to Chemistry in its element brought to you by Chemistry World , the magazine of the Royal Society of Chemistry.
And welcome to Chemistry in its element, where we take a look at the stories behind the elements that make up the world around us. I'm Chris Smith. This week, we are continuing our tour of the periodic table with a lung full of a gas that we can't do without. It protects us from solar radiation, it keeps us alive and by helping things to burn, it also keeps us warm.
It is of course oxygen. And to tell its story, here's Mark Peplow. Little did those humble cyanobacteria realize what they were doing when two and a half billion years ago, they started to build up their own reserves of energy-rich chemicals, by combining water and carbon dioxide.
Powered by sunlight, they spent the next two billion years terraforming our entire planet with the waste products of their photosynthesis, a rather toxic gas called oxygen. In fact, those industrious bugs are ultimately responsible for the diversity of life, we see around us today.
Overall, it's the most abundant element on the earth's surface and the third most abundant in the universe after hydrogen and helium. Oxygen is also in virtually every molecule in your body including fats, carbohydrates and DNA. In particular, it's the atom that links together the phosphate groups in the energy-carrying molecule ATP. Oxygen is obviously pretty useful for keeping us going, but is also widely used in industry as an oxidant, where it can give up some of that solar energy captured by plant and those cyanobacteria.
A stream of oxygen can push the temperature of a blast furnace over degrees and it allows an oxyacetylene torch to cut straight through metal. The space shuttle is carried into space on an incredible force produced when liquid oxygen and liquid hydrogen combine to make water. So who first noticed this ubiquitous stuff?
There's certainly some debate about who first identified oxygen as an element, partly because at the time the precise definition of an element still hadn't really been pinned down. English chemist, Joseph Priestley certainly isolated oxygen gas in the s, although he tried to define it as dephlogisticated air.
Phlogiston was then thought to be some kind of primordial substance that was the root cause of combustion. Swedish chemist, Carl Wilhelm Scheele was a fan of phlogiston too and probably discovered oxygen before Priestly did. But it was Antoine Lavoisier, sometimes called the father of modern chemistry, who was the first to truly identify oxygen as an element and in doing so, he really helped to firm up the definition that an element is something that cannot be broken down by any kind of chemical analysis.
This also helped him to kill off the phlogiston theory, which was a crucial step in the evolution of chemistry. Oxygen isn't only about the dioxygen molecules that sustain us. There is another form, trioxygen, also known as ozone and it's also pretty important in the upper reaches of the atmosphere, is responsible for filtering out harmful ultraviolet rays, but unfortunately, ozone is also pretty toxic.
So it's bad news that tons of the gas are produced by the reactions between hydrocarbons and nitrogen oxides churned out by cars every day. If only we could transplant the stuff, straight up into the stratosphere! Now ozone is normally spread so thinly in the air, that you can't see its pale blue colour and oxygen gas is colourless unless you liquefy it, but there is one place where you can see the gas in all its glory.
The aurora or polar lights, where particles from the solar wind slam into oxygen molecules in the upper atmosphere to produce the swirling green and red colours that have entranced humans for millennia.
So why life is a gas, that was Mark Peplow revealing the secrets of the element that we can't live without. Next time on Chemistry in its element, Johnny Ball joins us to tell the story of a chemical that's craved by Olympic athletes, makes good hi-five connectors and is also a favourite for fillings. And that's in teeth, not pies.
The gold colour in Buckingham Palace fence is actually gold; gold covered because it lasts 30 years; whereas gold paint which actually contains no gold at all lasts in tip-top condition only a year or so. So all that glitters isn't gold, but some is, and you can find out why on next week's Chemistry in its element. I'm Chris Smith, thanks for listening. See you next time. Chemistry in its element is brought to you by the Royal Society of Chemistry and produced by thenakedscientists.
There's more information and other episodes of Chemistry in its element on our website at chemistryworld. Click here to view videos about Oxygen. View videos about. Help Text. Learn Chemistry : Your single route to hundreds of free-to-access chemistry teaching resources.
We hope that you enjoy your visit to this Site. We welcome your feedback. Data W. Haynes, ed. Version 1. Coursey, D. Schwab, J. Tsai, and R. Dragoset, Atomic Weights and Isotopic Compositions version 4. Periodic Table of Videos , accessed December Consult your teacher or other knowledgeable adults and experts about how to obtain the mentioned materials and how to use them properly and safely in this experiment.
Do not do this experiment alone! Consult the link section and further resources provided. Ensure that you understand the basic principals. Surf the web and consult your local library, your teacher and other knowledgeable adults and experts. Oxygen from Plants In August of , Joseph Priestley , put a sprig of mint into a transparent closed space with a candle that burned out the air until it soon went out. After 27 days, he relit the extinguished candle again and it burned perfectly well in the air that previously would not support it.
And how did Priestley light the candle if it was placed in a closed space? He focused sun light beams with a mirror onto the candle wick Priestley had no bright source of light, and had to rely on the sun. Today, of course, we can use more sophisticated methods to light the candle like focusing light from a flood light through converging lens, or by an electrical spark.
So priestly proved that plants somehow change the composition of the air. In another celebrated Experiment from , Priestley kept a mouse in a jar of air until it collapsed. Priestley was a teacher, political philosopher, essayist, Unitarian minister and pioneer in chemical and electrical science. He discovered 9 gases including nitrous oxide.
He invented soda water, refrigeration, and gum erasers for which he coined the term "rubber". He discovered photosynthesis. He was humorless, argumentative, brilliant and passionate, called a "furious free-thinker".
While his liberal colleagues Josiah Wedgwood, Erasmus Darwin, James Watts, and others of the Lunar Society were celebrating the 2nd anniversary of the French revolution, a Birmingham mob, supported by the royalists and the established church, destroyed Priestley's home, laboratory and church.
Driven from England, he emigrated to Pennsylvania where he built a home and laboratory and collected a volume library, then among the largest in America. He is regarded as a founder of liberal Unitarian thinking.
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