Carbon dioxide in soil air

Lovell J. S. (2000) Oxygen and carbon dioxide in soil air. In Handbook of Exploration Geochemistry, Geochemical Remote Sensing of the Subsurface (ed. M. Hale). Elsevier, Amsterdam, vol. 7, pp. 451-469. 

Oxygen and carbon dioxide in soil air SAMPLING AND ANALYTICAL METHODS... 

Fig. 14-5. Relation of carbon dioxide in soil air and geology at Balei gold veins, Baykal region, Russia (reproduced with permission from Kulikova, I960).

Fig. 14-7. Oxygen and carbon dioxide in soil air over the Filizchai pyrite deposit, Azerbaijan (reproduced with permission from Dadashev et al., 1971).

Fig. 14-11. Carbon dioxide in soil air (sample sites and contours in %) over mineralised breccia pipe, northern Arizona (from Lovell and Reid, 1989).

Vinegar is recommended for cleaning a variety of appliances and other items that may be stained by hard water deposits. Automatic coffee makers, steam irons, dishwashers, teapots, faucet heads, and shower heads — over time, all accumulate calcium deposits from hard water. Groundwater, that is, water that travels through soil and rocks, accumulates dissolved calcium ions as a consequence of the natural weathering of minerals that contain calcium such as limestone and calcite, shells, and coral. At the same time, carbon dioxide in the air dissolves in water to form carbonate ions that combine with calcium ions to form a white solid, calcium... 

Farmers use lime (calcium hydroxide) to sweeten" an acid soil, and make heavy, clay-laden soils more workable. Carbon dioxide in the air dissolves in water to form the very weak carbonic acid (hydrogen carbonate). The alkaline lime neutralizes any traces of carbonic acid in the earth, producing calcium carbonate (or chalk) - and some more water. 

If you collect rainwater in a relatively unpolluted area, you will discover that the rainwater is essentially a nonconductor of electricity. A small concentration of carbonic acid from the carbon dioxide in the air added to the rainwater causes the rain water to be a weak conductor. Pure rainwater conducts almost as poorly as distilled water. However, most of the water we use comes from wells, lakes, or rivers. This water has been in contact with soil and rocks, which contain ionic compounds that dissolve in the water. Consequently, tap water conducts electricity. The conduction is not high, but the water can conduct enough current to stop a person s heart. So, for example, a person should not use an electrical appliance when in the bathtub or shower. 

Typically, acid soils are titrated with a sodium or calcium hydroxide [NaOH or Ca(OH)2] solution and basic soils with hydrochloric acid (HC1), and pH changes are most commonly followed using a pH meter. Carbonates in basic soils release C02 during treatment with HC1, thus making the titration more difficult. For this reason, carbonates are often determined by other methods. It is important to keep in mind that basic solutions react with carbon dioxide in air and form insoluble carbonates. This means that either the basic titrant is standardized each day before use or the solution is protected from exposure to carbon dioxide in air. Specific descriptions of titrant preparation, primary standards, and the use of indicators and pH meters in titrations can be found in Harris [1] and in Skoog et al. [2],... 

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