Carbon dioxide, dissolved

Carbonation can be measured ia terms of volumes of carbon dioxide dissolved ia one Hter of beverage at a standard temperature and pressure (0°C, 101.3 kPa = 1 atm). One Hter of carbon dioxide dissolved ia one Hter of beverage has a carbonation volume of one. 

An interesting and novel use of a soHd desiccant, the reduction of cold condensate corrosion in automotive exhaust systems, illustrates a hybrid closed—open system. Internal corrosion occurs in mufflers when the water vapor in the exhaust condenses after the engine is turned off and the muffler cools. Carbon dioxide dissolves in the condensate to form an acidic soup. In an essentially closed static drying step, an acid- and heat-resistant desiccant located in the muffler adsorbs water vapor from the exhaust gas as it cools to prevent formation of corrosive acidic condensate. When the engine is restarted, the system becomes open, and the desiccant is regenerated by the hot exhaust gas to be ready for the next cooldown step (19). 

Example. A gas oil having a density of 0.84 grams per milliliter (37°AP1) is stored at 60°C (140°F) under a gas blanket of carbon dioxide (CO2) at a pressure of 1 atmosphere absolute. To estimate the amount of carbon dioxide dissolved in the gas oil at equilibrium, take the following steps ... 

Carbon dioxide dissolves in water to form a weak acid (carbonic acid), which reduces the pH of the solution and, consequently, increases its corrosivity. Corrosion caused by carbon dioxide is generally referred to as sweet corrosion, and results in pitting. The mechanism of carbon dioxide corrosion is as follows [197,198] ... 

Carbon dioxide dissolves in water to form carbonic acid... 

The most important property of the dissolved solids in fresh waters is whether or not they are such as to lead to the deposition of a protective film on the steel that will impede rusting. This is determined mainly by the amount of carbon dioxide dissolved in the water, so that the equilibrium between calcium carbonate, calcium bicarbonate and carbon dioxide, which has been studied by Tillmans and Heublein and others, is of fundamental significance. Since hard waters are more likely to deposit a protective calcareous scale than soft waters, they tend as a class to be less aggressive than these indeed, soft waters can often be rendered less corrosive by the simple expedient of treating them with lime (Section 2.3). 

The extent to which carbon dioxide dissolves is proportional to its partial pressure in the steam phase (Henry s Law). Also, C02 (like most gases) is less soluble in hot condensate than in cool condensate. 

Acids are added to soft drinks for extra bite. The primary acid used in colas is phosphoric acid, while the one used in citrus-flavored drinks is usually citric acid. Carbonated water (water that has the gas carbon dioxide dissolved in it under pressure) is also mildly acidic (it is chemically carbonic acid, H2C03). 

Carbonic acid is an important natural component of the environment because it is formed whenever carbon dioxide dissolves in lake water or seawater. In fact, the oceans provide one of the critical mechanisms for maintaining a constant concentration of carbon dioxide in the atmosphere. Carbonic acid takes part in two successive proton transfer equilibria ... 

Rain unaffected by human activity contains mostly weak acids and has a pH of 5.7. The primary acid present is carbonic acid, H2C03, a weak acid that results when atmospheric carbon dioxide dissolves in water. The major pollutants in acid rain are strong acids that arise from human activities. Atmospheric nitrogen and oxygen can react to form NO, but the endothermic reaction is spontaneous only at the high temperatures of automobile internal combustion engines and electrical power stations ... 

C04-0032. Carbonic acid, H2 CO3 (molecular model shown below), is a weak oxoacid that forms when carbon dioxide dissolves in water. Carbonic acid contains two acidic hydrogen atoms. Write the net ionic reaction that occurs when carbonic acid reacts with an excess of hydroxide ions. Draw a molecular picture of the process. 

Water often is a reagent in an aqueous equilibrium. For example, when carbon dioxide dissolves in water, it reacts with a water molecule to form carbonic acid ... 

Carbonated water contains carbonic acid, a diprotic acid that forms when carbon dioxide dissolves in water C02(g) +H2 0(/) H2 C03(c2 q) A typical carbonated beverage contains 0.050 M H2 CO3. Determine the concentrations of the ions present in this solution. 

Zammouri, A., Chanel, S., Muhr, L., and Grevillot, G., Displacement chromatography of amino acids by carbon dioxide dissolved in water, Ind. Eng. Chem. Res., 38, 4860, 1999. 

Fourthly living things do not just respond to the climate—they affect it as well. Plants consume carbon dioxide and produce oxygen through photosynthesis. Earthbound plants take carbon dioxide directly from the air drifting photosynthetic micro-organisms called phytoplankton use carbon dioxide dissolved in water. 

Whenever atmospheric carbon dioxide dissolves in groundwater or in the water of rivers, lakes, and glaciers, it also reacts with the water to form mild carbonic acid, which renders the water slightly acidic ... 

Neutral solutions also contain a dissolved salt, derived from the neutralization of the acid and the base (a salt is an ionic compound formed in a neutralization reaction and is composed of the cation of an alkali and the anion of an acid). When a solution of carbonic acid (formed when atmospheric carbon dioxide dissolves in water), for example, reacts with an alkaline solution of lime, the two solutions neutralize each other and form a salt, calcium carbonate ... 

Carbon dioxide-water systems play an important role in controlling the pH of alkaline and calcareous soils as well as adjusting solubility of most trace elements and their compounds. Carbon dioxide dissolves in water to form dissolved C02 and dissociated carbonic acid, H2CO30 ... 

Like carbon dioxide, (dissolved) ammonia can be sensed via the pH changes it induces when diffusing into a small cavity containing an internal buffer69,70. The same is true for sulfur dioxide71. Selectivity for one of these... 

Egg shells are made of calcium carbonate, CaCCE. The chicken ingeniously makes shells for its eggs by a process involving carbon dioxide dissolved in its blood, yielding carbonate ions which combine chemically with calcium ions. An equilibrium is soon established between these ions and solid chalk, according to... 

Although the erosive action of running water on soil and rock produces the majority of sediments, they may also result from a variety of chemical processes that take place in water. For example, carbon dioxide dissolved in water may react with calcium ions to form insoluble calcium carbonate ... 

In the ocean experiments, scientists pump carbon dioxide into the deep ocean, where it forms giant lakes of liquid carbon dioxide. Eventually, the carbon dioxide dissolves into the surrounding waters. However, it is unclear how such increased amounts of oceanic carbon would affect sea life and water chemistry. 

The second method is a similar procedure the cap of the product s container (plastic, glass or can) is punctured with a needle. Carbon dioxide is expelled from solution by vigorous shaking, and the headspace pressure is recorded. From the pressure rise, the volume of carbon dioxide dissolved in the product can be determined. This method is probably one of the most commonly used procedures for measuring carbonation however, the exact method used varies from one manufacturer to another. One supplier of this type of carbonation tester is Stevenson Reeves of Edinburgh, which also sells a slide rule to convert pressure rise measurements into carbonation levels. Information about their products can be found on their website (http //www.stevenson-reeves.co.uk). 

Acids that contain more than one dissociable proton are called polyprotic acids. Polyprotic acids dissociate in a stepwise manner, and each dissociation step is characterized by its own acid-dissociation constant, Kal, Ka2, and so forth. For example, carbonic acid (H2C03), the diprotic acid that forms when gaseous carbon dioxide dissolves in water, is important in maintaining a constant pH in human blood. It undergoes the following dissociation reactions ... 

Soda is an example of a gas, carbon dioxide, dissolved in liquid water. 

At the feed side of the membrane, carbon dioxide dissolves in the aqueous carbonate/bicarbonate solution and reacts with water and carbonate ions according to Equations (11.21) and (11.23). 

Pressure has a dramatic affect on the solubility of gaseous solutes in liquid solvents. As pressure increases, the solubility of a gaseous solute in a liquid solvent increases. You have no doubt observed this phenomenon when opening a carbonated beverage. Have you noticed that when you open a bottle of champagne (or soda pop, or beer, or club soda), small bubbles of carbon dioxide gas start to form That pop you hear when removing the cork is caused by the escape of excess carbon dioxide gas from the bottle. When the gas escapes, the pressure in the container decreases. With less pressure, the solubility of the carbon dioxide dissolved in the wine decreases. As the carbon dioxide comes out of the solution, it forms those tiny (wonderful) little bubbles. Since solids and liquids are not very compressible, at least not compared to gases, pressure has very little effect on the solubility of solid and liquid solutes. 

When carbon dioxide dissolves in water, it combines with a water molecule to give carbonic acid. Notice that the reverse direction corresponds to stripping a water molecule away from carbonic acid, leaving carbon dioxide. 

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