Carbon dioxide dissociative

For hydrogen and carbon monoxide the cell equilibrium was identical to the single product, water or carbon dioxide, dissociation into the reactants. 

Carbon dioxide dissociates at high temperatures according to the following equation ... 

Dissociation of C02 at high temperature. Carbon dioxide dissociates into CO and O at high temperature as follows ... 

TABLE 7.5 Carbon Dioxide Dissociation Pressures of Sodium Hydrogen Carbonate and Calcium and Sodium Carbonates"... 

As an example of this, we may first consider the system formed by the two components CaO and CO2, which can combine to form the compound CaCO. This substance, on being heated, dissociates into calcium oxide and carbon dioxide, and gives rise to the equilibrium CaCOa CaO + COg, In accordance with the definition given on p. 6, there are present here two solid phases, the carbonate and the quicklime, and one vapour phase the system is therefore univariant. To each temperature, therefore, there will correspond a certain definite maximum pressure of carbon dioxide (dissociation pressure) and this... 

We have seen from methane transient experiments that it dissociates over Pt leaving carbon behind and generating hydrogen in the gas phase. If carbon dioxide dissociation occurs in a concerted... 

The carbon dioxide dissociation pressure for calcite is shown in Table 3.2. At approximately 900 °C, the pressure reaches 1 atmosphere [3.11] — this is generally referred to as the decomposition temperature of calcium carbonate. The decompositions of dolomite and dolomitic limestones are complex and are described more fully in section 15.2. 

Figure 5-9. Energy efficiency of carbon dioxide dissociation by means of electronic excitation of the molecules as functions of reduced electric field (1) contribution of singlet states (including...

Polak, L.S., Slovetsky, D.I., Butylkin, Yu.P (1977), Carbon Dioxide Dissociation in Electric Discharges Arc Discharge, Institute of Petrochemical Synthesis, USSR Academy of Sciences, Moscow. 

As an example of an acid-base equilibrium problem, consider water in equilibrium with atmospheric carbon dioxide. The value of [COj (aq)] in water at 25°C in equilibrium with air that is 390 parts per million COj (close to the concentration of this gas in the atmosphere) is 1.277 X 10 mol/L. The carbon dioxide dissociates partially in water to produce equal concentrations of H+ and HCO3" ... 

Ionization of water Dissociation of water Hydroxylation of bisulphide Dissociation of carbon dioxide Dissociation of bicarbonate ... 

As explained in Chapter 6, the blood line on this plot is closely related to the carbon dioxide dissociation curve of the blood, a fact which allows acid-base physiology to be related directly to the carriage of carbon dioxide in the blood and thence to respiratory physiology. 

ACID-BASE BALANCE AND THE CARBON-DIOXIDE DISSOCIATION CURVE OF THE BLOOD... 

In plots of acid-base status, bicarbonate was displayed as a function of the partial pressure of carbon dioxide. One of the reasons for choosing this pair of variables is that the graph given for blood on the acid-base status plot is very similar to the carbon dioxide dissociation curve for the blood. The carbon dioxide dissociation curve is the relationship between the partial pressure with which blood is in equilibrium and the amount of carbon dioxide which the blood holds. 

To determine the carbon dioxide dissociation curve, one proceeds as follows. A sample of blood is equilibrated with a gas mixture containing a known partial pressure of carbon dioxide this value is plotted as the x-coordinate. A strong acid such as hydrochloric acid is then added and the blood is exposed to a vacuum to drive off all the carbon dioxide. The amount of carbon dioxide extracted is measured and plotted as the y-coordinate to yield one point on the graph. The procedure is repeated on samples of blood at various values of carbon dioxide partial pressure. At each PCO2 the content is measured and the points on the graph are joined to give the dissociation curve (Figure 6,4). 

Figure 6.4. Carbon dioxide dissociation curves for oxygenated and deoxygenated blood. 

COMPARISON OF THE OXYGEN AND CARBON DIOXIDE DISSOCIATION CURVES OF BLOOD... 

Figure 6.6. The physiological carbon dioxide dissociation curve for a normal person at rest. The points A and V represent partial pressures and contents of arterial and mixed venous blood respectively. As with the oxygen dissociation curve, this physiological carbon dioxide dissociation curve-moves between the two curves plotted with constant partial pressures of oxygen corresponding to oxygenated and deoxygenated blood.

Figure 6.9B, which shows the oxygen and carbon dioxide dissociation curves for blood together, illustrates how much more carbon dioxide than oxygen is held by the blood. The points corresponding to the eupnoeic state are labelled Normal those for hypoventilation are labelled Hypo and those for hyper-... 

E. The shift in the carbon dioxide dissociation curve by oxygenation of the blood is because of altered affinity of haemoglobin for hydrogen ions. 

Draw the oxygen and carbon dioxide dissociation curves blood. For each, indicate and explain the significance of a change in partial pressure of the other gas. 

Show and explain the physiological oxygen and carbon dioxide dissociation curves for blood passing through systemic or pulmonary capillaries. Indicate and give the coordinates of points representing arterial and mixed venous blood. 

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