Limestone, carbon dioxide release from

The greater the amount of carbon dioxide in soil, the more hydronium ions and so the lower the pH. Soil that has a low pH is referred to as sour. (Recall from Chapter 10 that many acidic foods, such as lemon, are characteristically sour.) Two main sources of soil carbon dioxide are humus and plant roots. The humus releases carbon dioxide as it decays, and plant roots release carbon dioxide as a product of cellular respiration. A healthy soil may have enough carbon dioxide released from these processes to give a pH range from about 4 to 7- If the soil becomes too acidic, a weak base, such as calcium carbonate (known as lime or limestone), can be added. 

Organic matter not only plays a direct role as a source of calcium and magnesium, but it is also a food for microorganisms that form carbon dioxide and many organic acids, such as acetic, butyric, lactic and oxalic. These acids react with limestones and other minerals and thereby continually release available nutrients. In the presence of an abundant supply of humus much of the released calcium and magnesium that is not immediately absorbed by plants may be adsorbed by the humus and thereby be prevented from loss by leaching. ... 

Carbon is not secure from an inorganic chemist s Periodic-Table-scanning eyes. Some of the simpler compounds of carbon, such as the carbon dioxide that I have already mentioned, the killer gas carbon monoxide, and chalk and limestone that form our landscapes, are readily released by organic chemists from their domain as being of little interest to them and by convention are regarded as inorganic. On the frontier between the divisions, though, lie compounds that are intricate assemblies of carbon atoms yet include atoms of various metals. A number of these compounds are essential catalysts in the chemical industry ... 

To stem the release of radioactive material from the reactor and to ensure that reactivity did not rise again to dangerous levels, sand, lead, dolomite and limestone (to release carbon dioxide to extinguish graphite fires), clay and boron compounds, were dropped from Soviet army helicopters on to the reactor core. 

One way to reduce the quantity of SO2 released into the environment is to remove sulfur from coal and oil before these fuels are burned. Although difficult and expensive, several methods have been developed. Powdered limestone (CaC03), for example, can be injected into the furnace of a power plant, where it decomposes into lime (CaO) and carbon dioxide ... 

Limestone (calcium carbonate, CaCOj) is a common sedimentary rock that was laid down eons ago on ocean floors, mostly from the remains of decomposed marine organisms. Subsequent uplift of the land brought limestone above sea level. Carbon dioxide dissolved in rainwater undergoes the reactions shown above. The natural acidity of rainwater lends itself to slightly dissolving limestone, releasing calcium ions (Ca ) into the environment, as shown ... 

Frasch s creative mind continued to work on petroleum. Between 1880 and 1900, thirty-four patents were filed by Standard Oil, half of which originated with Frasch. In 1895, another major invention was made by Frasch, the acidizing of an oil well to increase production, but this was not for Standard. Patents for the process were issued the following year (U.S. patent 556,651, 556,669). The acid reacted with the limestone rock, releasing carbon dioxide gas that opened up fissures in the rock. This process freed trapped oil pockets. Frasch had worked on this project with John W. Van Dyke (1849 - 1939). Frasch had known Van Dyke from the Solar Refinery years, where the latter had been the Superintendent of the revolutionary refinery for sour oil. On April 1, 1896, they assigned the patents to Van Dyke s company, the Oil Well Acid Treatment Company of Lima, Ohio. Van Dyke later led the Standard Oil spin-off company, the Atlantic Refining Company (later becoming part of ARCO and now part of BP). 

Relative to the other three compartments, however, organisms dramatically increase the overall rate and complexity of chemical cycling. Consider the geochemical cycling of calcium. Exposure of calcium-bearing rocks to water allows the calcium to become ionized and released into solution. The ionized calcium (Ca +) reacts with dissolved carbon dioxide (CO2) to form calcium carbonate, or limestone, which settles out in solid phase, where it can remain for hundreds of millions of years. Animals have exploited this comparatively simple phase transition from ionized calcium in water to the production of calcium carbonate, and they have incorporated the salt... 

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