Chemistry+Applications+Essay+57

Chemistry Applications Essay
 * Charlie West **
 * Chem 1 H **
 * Mr. Ceccarelli **


 * Sinkholes are large holes in the ground often caused by erosion, mine collapses and the dissolution of any carbonate rock by groundwater. Sinkholes range in size from a couple feet to acres wide. They can also range from a small concave pit to a deep hole with vertical walls. While some of the most impressive sinkholes occur in China or Venezuela, many states such as Florida and Pennsylvania are also affected. A landscape with rock that can be dissolved and many sinkholes is called a karst landscape. One of the most common sinkhole rocks, found in many karst landscapes, limestone, is Calcium carbonate/CaCO3. This can be easily broken down when in the presence of an acid. The groundwater that comes in contact with it is naturally acidic with a ph of 5 or 6. The limestone is then broken down into Ca2+ and CO3 2-. This CO3 2- readily combines with H+ to create HCO3 -. This process repeats and gradually the groundwater dissolves more and more limestone creating huge cavities in the ground. The problem comes when the ground above is not stable anymore and it collapses in on the void. Another process that creates many sinkholes is suffosion. This occurs when loose material, like soil and clay, underneath the ground is washed away. Sinkholes caused by suffosion usually occur more slowly over time while dissolution sinkholes happen suddenly. A sudden collapse can be extremely dangerous, especially in urban settings, since sinkholes can swallow whole houses and cars. It is amazing to see how just such a simple process of something like dissolution or suffosion can have such a large impact on the landscape and the people that reside there. **

** __Citations__  **
 * Farrant, Andrew. "Dolines and Sinkholes." British Geological Survey Website. National Environment Research Council, n.d. Web. 04 Jan. 2013. **


 * Pavils, Gatis. "Most Impressive Sinkholes of the World." Wondermondo. Wondermondo, n.d. Web. 4 Jan. 2013. **


 * Perlman, Howard. "Sinkholes." USGS. USGS Water-Science School, 11 Dec. 2012. Web. 04 Jan. 2013. **