is oxygen the most abundant element on earth? (i know it is in the crust?!?)?
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It makes up 46ish% of the crust (followed by silicon, aluminium, iron, calcium, sodium, potassium, magnesium and some others).\nIt isn't as abundant in the air though (Nitrogen, Oxygen, Argon Carbon dioxide, others), about 20%.\n\nThe most abundant elements are Hydrogen, Helium, Oxygen, Neon, Nitrogen, Carbon, Silicon, Magnesium, Iron and Sulpher.
385679
Osmium is the densest matter here on planet earth if I recall correctly from chemistry.  Black holes, white dwarves, neutron stars, the big bang singularity... Are all working theories at this point.  Since we can't simulate them in a lab and can't travel to them to sample them, we are stuck with mathematical testing.  So if you want something that you could pick up (you might need a protective suit), then it is osmium.  Otherwise the highest density occurred about 15 billion years ago at the start of the big bang.
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HISTORY OF OXYGEN\n\nIt's difficult to think of free oxygen, which makes up 21 percent of earth's atmosphere, as a poisonous gas. Virtually all organisms alive today need oxygen to survive. Even plants, which expel oxygen into the atmosphere, need oxygen to live. There was a time early in earth's history, however, when living organisms not only did not need oxygen, but were killed when exposed to the element. \n\nThree and a half billion years ago, Earth's atmosphere contained almost no free oxygen. Instead, it consisted mainly of carbon dioxide, perhaps as much as 100 times more carbon dioxide than contained in today's atmosphere. During this time, Earth's only life forms were aquatic, one-celled organisms -- primitive forms of bacteria -- that extracted energy from a variety of sources. To most of these organisms, free oxygen was poisonous. \n\nAt about the same time, new types of primitive bacteria evolved. Unlike their predecessors, these bacteria could convert energy directly from the Sun, through photosynthesis. One type, bluish-green organisms called cyanobacteria, used sunlight to convert carbon dioxide and water into glucose (sugar). These organisms expelled oxygen gas -- a by-product of photosynthesis -- into the oceans. \n\nAs the cyanobacteria multiplied and spread around the globe, they released more and more free oxygen into the oceans. This oxygen combined with the molecules of living bacteria, killing them off as it did so. It also combined with other matter, such as the iron dissolved in the ocean. Only after the oxygen combined with all of the matter available did free oxygen begin to accumulate in the oceans. And when the oceans became saturated with oxygen, it began to make its way into the atmosphere. \n\nOrganisms that don't need free oxygen to survive are called anaerobic; all living things that need free oxygen, including us, are aerobic organisms. As the oceans and atmosphere filled with oxygen gas, aerobic life evolved further, at some point adding a nucleus to the cell (to protect the cell's DNA from the harmful effects of oxygen) and eventually to multi-cellular organisms. Anaerobic life, on the other hand, was pushed back to areas where there was little or no oxygen. Today, anaerobic organisms like those that existed more than three and a half billion years ago live in oxygen-free places such as volcanic hot vents, where they get their energy in ways other than from carbon dioxide, water, and sunlight.\n\nIMPORTANCE OF OXYGEN\n\nCirculatory System, or cardiovascular system, in humans, the combined function of the heart, blood, and blood vessels to transport oxygen and nutrients to organs and tissues throughout the body and carry away waste products. Among its vital functions, the circulatory system increases the flow of blood to meet increased energy demands during exercise and regulates body temperature. In addition, when foreign substances or organisms invade the body, the circulatory system swiftly conveys disease-fighting elements of the immune system, such as white blood cells and antibodies, to regions under attack. Also, in the case of injury or bleeding, the circulatory system sends clotting cells and proteins to the affected site, which quickly stop bleeding and promote healing.\n\nRespiratory System, in anatomy and physiology, organs that deliver oxygen to the circulatory system for transport to all body cells. Oxygen is essential for cells, which use this vital substance to liberate the energy needed for cellular activities. In addition to supplying oxygen, the respiratory system aids in removing of carbon dioxide, preventing the lethal buildup of this waste product in body tissues. Day-in and day-out, without the prompt of conscious thought, the respiratory system carries out its life-sustaining activities. If the respiratory system’s tasks are interrupted for more than a few minutes, serious, irreversible damage to tissues occurs, followed by the failu
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Osmium is the densest element. 22.6 g/ml\nhttp://www.science.uwaterloo.ca/~cchieh/cact/c120/qzelemnt.html
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It's widely believed in the scientific community that the earth has a liquid mantle (that's where magma/lava comes from) and a solid super-hot iron core.  Good luck digging through that.
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The paper cited below says "It is the rarest element with an amount of only 550 g. in the entire earth's crust,"\n\nThat's a little more than 18 atoms.
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Many materials can react with ozone to form oxygen as a by-product.  Most all are reducing agents.  A more definitive answer rests on how you are using the term "element".  If you are using it the periodic table sense then your answer would include many of the metals capable of being oxidized.
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The earth's crust is composed of Quartz, SiO2, or Silicon Oxide, and Feldspar......both are contained in Granite......The earth's crust is made of Metamorphic rock mainly....
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Yes. Everything is a chemical element.\n\nCSO2 I believe.
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It isn't always found.\n\nBut it is very, very rare on Earth's surface because it collected mainly in the phase of Earths history when it was molten, and so is mainly present only in the core now.\n\nBy contrast, meteorites which are often made of similar material to that which Earth condensed out of are often relatively abundant in it.
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Well, you are getting in to a bit more complicated chemistry. For the question you are asking, the simple answer is No. However there are multi-valence ions, such as Oxygen. Normally Oxygen would gain 2 electrons making it O(2-) but it has another valence of 1 where it only gains one electron and becomes O(1-). By the sounds of it you are not at this point so don't worry about but you will get there eventually. In order to understand multi-valence you need a Periodic Table of Elements that lists all the valences of each element. This makes bonding harder, etc,etc so I wouldn't worry about it if I were you, yet.\n\nSo to simply answer your question, No, it is impossible for Magnesium
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Nitrogen is the most abundent element in our atmosphere.  Bacteria gets N2 from the air.
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Nitrogen might be what you are looking for as it is a gas and is next to Oxygen in the periodic table so it has similar mass.\n\nBut as the person above has said, some kind of gaseous sulfur would have the closest properties to oxygen.
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Si is the most abundant mineral element, but feldspar would be the most abundant mineral as far as rocks & minerals. Quartz comes in second.
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Most of the earth is made of iron and nickel.  This might not appear to be true at first because we see that the ground does not feel like metal, but the earth's inner and outer cores consist primarily of molten iron and nickel.  The earth's crust is only a few miles thick (at the thickest) and floats on top of the molten layers.
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Solid Phase,Silicon makes up 25.7% of the earth's crust and is the second most abundant element on Earth, after oxygen. Elemental silicon is not found in nature. It occurs most often as oxides and as silicates. Sand, amethyst, agate, quartz, rock crystal, flint, jasper, and opal are some of the forms in which the oxide appears. Granite, asbestos, feldspar, clay, hornblende, and mica are a few of the many silicate minerals.\n\nhttp://periodic.lanl.gov/elements/14.html
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Carbon, Iron and Nickle. In that order I believe. \n\nThat is of the earth itself... If you mean of the planet including the atmosphere, then its Hydrogen and Helium.