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Founded in 1879 and named after Texas' greatest hero General Sam Houston, Sam Houston State University is public shcool within the Texas state university system and located in Huntsville, Texas.
It's a multicultural institution that offers 79 bachelorette degree programs, 54 masters and five ...
The structural arrangement of rocks in any crust of a planet. Used to understand rock structures.
Industry:Chemistry; Weather
This is the area between 30ƒ and 35ƒ latitude where the dense cool air descends and the winds become weak. According to some traditions sailors relying solely on wind power threw their horses overboard in hopes that speed would increase due to the resulting lighter load of the ship. Other traditions state that the horses were thrown overboard to avoid depleting their provisions and still another states that this is simply the region where the horses perished.
Industry:Chemistry; Weather
The systematic numbering system originally created by the Du Pont Chemical Company in the early 1930s, which is now the standard method in the naming of chlorofluorocarbons (CFCs). Chlorofluorocarbons, such as dichlorodifluoromethane (CCl<sub>2</sub>F<sub>2</sub>), and trichlorofluorocarbon (CCl<sub>3</sub>F), were given the nicknames CFC-12 and CFC-11, respectively, by Du Pont so that they could be remembered more easily. In order to derive the chemical structure of a chlorofluorocarbon from its common name, the rule of 90 states that you would add 90 to the number at the end of the name. In the case of CFC-12, add 90+12 to get 102. The hundreds place, the one in this example, represents the number of carbon atoms in the molecule. The tens place, the 0, represents the number of hydrogen atoms in the molecule, and the ones place represents the number of fluorine atoms in the molecule. According to the rule of 90, CFC-12 has 1 carbon atom, 0 hydrogen atoms, and 2 fluorine atoms. The final aspect of the rule of 90 pertains to the necessity of carbon to form four bonds. If, after assigning hydrogen and fluorine atoms to it, the carbon atom still requires more bonds to reach the required four, those bonds will be to chlorine atoms. So far, the one carbon atom of CFC-12 has only formed two bonds, both with fluorine atoms. Thus the remaining two bonds must be chlorine atoms. Analogously, CFC-11's chemical formula is CCl<sub>3</sub>F.
Industry:Chemistry; Weather
The thermal atmospheric region of the atmosphere between the troposphere and the mesosphere. The lower boundary of the stratospheric region is marked by the tropopause and begins at approximately 13 kilometers; however, this altitude of the troposphere depends on latitude. The upper limit of the stratosphere is marked by the stratopause at approximately 50 kilometers. The stratosphere is characterized by relatively stable temperatures (between -80 and -50 degrees Celsius) in the lower regions, and begins warming near 20 kilometers, reaching its maximum temperature of approximately 0 degree Celsius at the stratopause. Stratospheric chemistry is of particular interest to scientists because ozone, the principal substance that shields the earth from incoming solar ultraviolet radiation, is found in the stratosphere. It should also be noted that wind currents in the stratosphere are primarily horizontal in nature.
Industry:Chemistry; Weather
The rising of air as it moves through the atmosphere based upon density differences. Cold air is denser than warn air. The air which has a lower density will float or be lifted over the air which is more dense while moving toward air of the same density. That is why hot air rises by following an upward-sloping movement through the atmosphere while cool air sinks. `
Industry:Chemistry; Weather
The process of the change in the state of a liquid or solid to a gas or vapor. Vanishing of the surface of a liquid to the atmosphere.
Industry:Chemistry; Weather
Ultraviolet light that has wavelengths of 320 nm to 400 nm. The wavelengths of this light are shorter than visible light and are not absorbed in the stratosphere by ozone.
Industry:Chemistry; Weather
This is a gap in the atmosphere's spectral absorption. It is created because not enough molecules in the atmosphere are absorb in the wavelengths 8-12 micrometers. Absorption is caused by the molecules in the air, therefore adding more gases to the atmosphere the window can become reduced and cause more of these wavelengths to stay in earths atmosphere causing global warming.
Industry:Chemistry; Weather
Two or more forms of an element that have the same atomic number but different numbers of neutrons in the atomic nucleus and therefore a different atomic weight. Most elements occur naturally as mixtures of isotopes. The symbol for an isotope usually consist of the mass number placed as a leading superscript before the elemental symbol. In atmospheric chemistry, long lived isotopes such as carbon-14 (<sup>14</sup>C) are used to determine the age of objects that contained living matter. Other isotopes are used to track the routes of air parcels in the atmosphere.
Industry:Chemistry; Weather
Two or more radical species reacting to form non-radical products; the nighttime reaction of nitrogen dioxide radical with ozone to produce neutral nitrogen pentoxide is an example of radical termination:
NO<sub>2</sub> + O<sub>3</sub> ---> NO<sub>3</sub> + O<sub>2</sub> then
NO<sub>2</sub> + NO<sub>3</sub> ---> N<sub>2</sub>O<sub>5</sub>
Industry:Chemistry; Weather
