What are the two main gases found in Earth's atmosphere?
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Nitrogen (N2) 780,840 ppmv (78.084%) \nOxygen (O2) 209,460 ppmv (20.946%)
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Like all matter, the atmosphere is heated by the suns light.  When light is absorbed by the earth (the ground, the ocean, etc.) it is heated up (it's molecules move around faster) The air that makes up the atmosphere then absorbs some of the heat that is emitted by the earth.  When the air absorbs heat from the earth, this cools the earth.
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There are in fact many different atmospheric layers as you move upward away from the earth. However, there are NOT different layers of gases. All the gases are sort of mixed.\n\nThe troposphere, the atmospheric layer that we live in, contains the most gases. This is due to gravity. Anything that has mass will be attracted to earth's gravity.\n\nThat is why when you move away from the earth there is less air. Less gravity = less air!\n\nThe higher you go in the troposphere, the colder it gets. That is also due to less air (holds heat).\n\nThe next layer up is the stratosphere. This layer is where most jets fly & where the atmospheric ozone layer exists.\n\nTemperatures in the stratosphere will get warmer due to the ozone layer. Ozone is an insulator & traps heat.\n\nAs you move higher, you will reach the mesosphere. And, as you may have already guessed, this layer contains even less air. It also gets pretty darn cold as you move away from the ozone layer. "Shooting stars" occur in this layer. Meteorites burn up as they enter our atmosphere.\n\nThe last layer is called the thermosphere. It has the least amount of air. But the odd thing is that this is the hottest layer!!!\n\nSounds strange??? Well here is why...\n\nAlthough there is less air to hold heat, there is still some present. Mind you, it is few & far between. Imagine being in the Astrodome & someone across the field threw a BB at you! That is how sparse the air particles are.\n\nHowever, we have said there is air! That air that is present is constantly bombarded with nasty cosmic rays! By this time, here is so much energy in the air particles that the temperature is astronomical (no pun intended).\n\nBecause of this, the thermosphere is often called the "heat sphere", just as it's name implies.\n\nSatellites are put into orbit in the thermosphere.\n\nTo get directly to your question... there are different layers because scientists decided to name them according to temperature changes.
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The Earth's atmosphere has no definite boundary, slowly becoming thinner and fading into outer space. Three-quarters of the atmosphere's mass is contained within the first 11 km of the planet's surface. This lowest layer is called the troposphere. Further up, the atmosphere is usually divided into the stratosphere, mesosphere, and thermosphere. Beyond these, the exosphere thins out into the magnetosphere (where the Earth's magnetic fields interact with the solar wind). An important part of the atmosphere for life on Earth is the ozone layer.\n\nThe atmospheric pressure on the surface of the Earth averages 101.325 kPa, with a scale height of about 6 km. It is 78% nitrogen and 21% oxygen, with trace amounts of other gaseous molecules such as water vapor. The atmosphere protects the Earth's life forms by absorbing ultraviolet solar radiation, moderating temperature, transporting water vapor, and providing useful gases. The atmosphere is one of the principal components in determining weather and climate.\n\nBecause hydrogen gas is light and based on Earth's mean temperature, achieves escape velocity, unfixed hydrogen leaves the Earth. For this reason, the Earth's environment is oxidizing, with consequences for the chemical nature of life which developed on the planet.\n\nYou could get more information from the link below...
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The nitrogen gas in air gets converted to 1) ammonia 2) nitrates (from nitrites)
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hey! Air is a mixture of gases thus it is solution, it contains Nitrogen-78%, oxygen-20.9% carbon dioxide0.003% and some rare gases
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They are the gases that trap heat in the Earth's atmosphere.  They are Carbon Dioxide and Methane.
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The Earth's primitive atmosphere was much different from today's and consisted primarily of ammonia, methane, and trace amounts of carbon dioxide and water vapor.  There was little, if any, free oxygen present.
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The Troposphere is the lowermost portion of Earth's atmosphere. It is the densest layer of the atmosphere and contains approximately 75% of the mass of the atmosphere and almost all the water vapour and aerosol.\n\nBecause of earth's attraction towards its centre,this troposphere,oxygen,water ,nitrogen ,carbon...etc all hold together.
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Carbon, Hydrogen, and Oxygen.
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climate or atmosphere
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Ozone: A molecule made up of three atoms of oxygen. Occurs naturally in the stratosphere and provides a protective layer shielding the Earth from harmful ultraviolet radiation. In the troposphere, it is a chemical oxidant, a greenhouse gas, and a major component of photochemical smog.\n\nOzone precursors: Chemical compounds, such as carbon monoxide, methane, nonmethane hydrocarbons, and nitrogen oxides, which in the presence of solar radiation react with other chemical compounds to form ozone.
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The atmosphere is 21% oxygen.  The process of separating the gases from each other is where the expense is.  They compress the gas and the cool it until it turns into a liquid.  Different gasses turn into a liquid at different temperatures.  Then they bottle it and ship it.
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The air is the gaseous compounds and elements that make up the Earth's atmosphere.\n\nThe essence of the air is that it is made up of mostly Nitrogen (78%), and also a fair amount of Oxygen (21%), plus Argon and a myriad of other gases including water vapour, ozone and carbon dioxide.\n\nOxygen is probably the most important element for humans, as our metabolism has evolved to utilize oxygen as the ultimate electron receptor in the biochemical pathway that provides the energy to run the metabolic processes that keep our body, and most importantly our energy hungry brain, operating.\n\nWithout oxygen, our body is forced to switch to the 'back-up generator' of anaerobic respiration, and that pathway simply doesn't provide enough energy to keep our body operating for very long.  It works fine for some bacteria, but we need a bit more oomph in our catabolism.\n\nThe atmosphere also shields us from some of the harmful effects of the radiation of our sun, such as ultraviolet radiation, and makes temperature and climate more stable, holding heat when the sun isn't shining on us, and taking longer to heat up when it is shining.  Thus it also makes our lives more comfortable.\n\nPlus if we didn't have the air, it wouldn't be there to refract light and make the sky blue, or form regions with big fluffy poofs of water vapour to scud lazily across the blue sky on a lazy summer afternoon, or provide a medium in which butterflies can dance prettily in summer air.\n\nSo I have no idea what 'quimic composition' is, but that's the essence of air.
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Primary(aprox. 46 billion years ago) atmhosphere was included hydrogen, helium and ammonia. \nSecondary (current) atmosphere eveolved as volcanic activity added nitrogen, water vapor and CO2 to the atmosphere. And appearance of green plants added free oxygen to the air. \nAdditionally there are some variable components of atmosphere:two imporatnt ones; water vapor and ozone. Permanent compnonets are NITROGEN, OXYGEN, ARGON and CO2.
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Iron. \n\nThat 46% figure for oxygen is not correct because it is only for the earth's crust. It does not include the mantle or the core. \n\nFor the entire planet iron makes up 35% of the mass of the planet and oxygen is only 30%. Silicon is 15%, magnesium 13%, and everything else is 7%. \n\nMy source is the USGS (which also cites the 46% oxygen for crust):\nhttp://pasadena.wr.usgs.gov/office/ganderson/es10/lectures/lecture04/lecture04.html
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Air is a mixture of atoms and molecules in the gaseous state.  A more technical term for the layers of gases surrounding the Earth is atmosphere. \n\nIf you are interested in what air   is made of and the way the chemicals in air combine and react with other chemicals, you would need to study chemistry.\n\nThe study of weather is meteorology, and would include studying wind and other weather patterns.\n\nThe study of the basic forces and motion of objects, including air would be considered physics.\n\nI have included one link to help you explore this fascinating subject.