![]() ![]() While this could be done by distillation of liquid air, membrane separation technologies are more modern and energy efficient. All that must be done is to separate the oxygen from the nitrogen. What is the cheapest way to obtain elemental oxygen? We lead the students to conclude that photosynthesis provides large amounts of oxygen and that air is a free feedstock. We decline that answer and note that the energy costs of such a process are prohibitive. Usually the immediate answer that is offered is electrolysis. We ask the class how oxygen is made in order to be used for all the purposes we described. Very quickly the students will realize that carbon monoxide is colorless, odorless and tasteless. ![]() Often there will be agreement until we ask what other colorless, odorless, tasteless gases there might be. We ask the class if these properties can be used to identify oxygen. Students will know that oxygen is a colorless, odorless gas (figure 1). It is used in the manufacture of steel (to remove sulfur, carbon, and phosphorus impurities that make iron brittle), paper, chemicals, rocket propellants, and in hospitals.įigure 1: Container of oxygen gas Physical Properties However, oxygen is also one of the highest production volume commodity chemicals. One can derive energy from combustion reactions anywhere on the planet. UsesĬlearly oxygen is essential for life! Further, it should be noted that combustion in its many forms powers human society, and that oxygen can be considered a global energy currency. They are likely to be unaware that most of the planet’s oxygen is to be found chemically combined in the rocks in the earth’s crust. Further “What else?” prodding usually leads to looks of puzzlement. When prodded “Where else?” they will answer that it occurs in water. Students will usually immediately respond correctly that oxygen is found in the atmosphere. A full class period is devoted to the discussion of oxygen and the accompanying demonstrations. By this point the students understand the Element of the Month program and have prepared a poster. The second element highlighted by our Element of the Month program is OXYGEN. Read The Element of the Month - An Introduction for an overview of the project and links to the other articles in the series." - Editor Folger (MRF), chemistry teacher (now retired) at Lyme – Old Lyme High School in Connecticut. Wright (SWW), Associate Research Fellow at Pfizer Inc., and Marsha R. "In honor of the International Year of the Periodic Table this series of articles details the Element of the Month project developed by Stephen W. ![]()
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