Antoine relationship

Systems that behave in this manner obey the Antoine relationship between pressure P and temperature T as represented by... 

The vapor pressure systems obey the Antoine relationships ... 

Two empirical parameters are evident in equation 7, the heat of vaporization and the integration constant, I. Experimental data indicate that the linear relationship suggested by Clausius-Clapeyron may not be followed over a large temperature range (4) therefore additional adjustable parameters have been added to equation 7 to improve its correlating abiUty. The most prominent of these is the Antoine equation ... 

Blanco et al. (1994) reported measurements of the vapor pressure (P,at) for p-xylene, y-picoline, piperidine, pyridine and tetralin. The data for piperidine and pyridine are given in Table 3.4. A suitable equation to correlate these data is Antoine s relationship given next... 

The French chemist, Antoine Lavoisier (1743-1794), was the first person to notice the gas-volume relationship. He observed water decomposing to give two volumes of hydrogen and one volume of oxygen. He mentioned this relationship in his 1789 textbook Elements de la Chemie. 

The bubble-point temperature may be calculated by trial and error as the value of Tbp that satisfies this equation all that is needed is a set of relationships for p T), such as the Antoine equation or vapor-pressure charts or tables. Once Tbp is known, the composition of the vapor phase can easily be determined by evaluating the partial pressures of each component from Equation 6.4-3 and determining each vapor-phase mole fraction as y, = pj P. 

Vapor Pressure The volatility of a given component is expressed by its vapor pressure, which increases with increasing temperature (Figure 2). The lower the vapor pressure, the lower the volatility and, thus, the more difficult to remove the component from the oil. For each specific component, the vapor pressure-temperature relationship can be expressed by the Equation of Antoine ... 

The study of quantitative relationships between amounts of reactants used and products formed by a chemical reaction is called stoichiometry. Stoichiometry is based on the law of conservation of mass, which was introduced by Antoine Lavoisier in the eighteenth century. The law states that matter is neither created nor destroyed in a chemical reaction. Chemical bonds in reactants break and new chemical bonds form to produce products, but the amount of matter present at the end of the reaction is the same as was present at the beginning. Therefore, the mass of the reactants equals the mass of the products. 

Useful correlations exist among the Antoine parameters (or at least relationships among them) and molecular structure. 

An atomic theory based on chemical concepts began to emerge from the work of Antoine Lavoisier (1743-1794), whose careful quantitative experiments led to an operational definition of an element An element was a substance that could not be decomposed by chemical processes. In other words, if a chemist could not decompose a substance, it must be an element. This point of view obviously put a premium on the ability of chemists to manipulate substances. Inspection of Lavoisier s fist of elements, published in 1789, shows a number of substances, such as silica (Si02), alumina (AI2O3), and baryta (BaO), which today are recognized as very stable compounds. The chemists of Lavoisier s time simply did not have the tools to decompose these substances further to silicon, aluminum, and barium, respectively. The composition of all compounds could be expressed in terms of the elemental substances, but it was the quantitative mass relationship of compounds that was the key to deducing the reality of the chemical atom. 

Frequently the Antoine equation [54] is used as a vapour pressure-temperature relationship ... 

This tradition was finally broken by Kepler who developed the contention of Pythagoras and Plato that a proportional relationship exists between polyhedron and circle. In time, this approach led to modern astronomy and, in the hands of Robert Boyle (1661) and Antoine Lavoisier (1789), to chemistry. However, the victory of science over magic has by no means been final . Modern big-bang cosmology, like the chain of assumptions in computational quantum chemistry (Rouvray, 2009), are rapidly reverting to the occult approach. An alternative model, emerging in chemistry, is based on the golden ratio, which both Kepler and Leonardo da Vinci referred to as the Divine Proportion. 

The ideal gas law characterizes the relationship between pressure, temperature, and volume for gases. Both the Clausius-Clapeyron and Antoine equations characterize the vapor-liquid equilibrium of pure components and mixtures. At atmospheric pressure and ambient temperature, water is a liquid but an equilibrium exists with its vapor phase concentration—its vapor pressure. The vapor pressure is a function of temperature. The formula for the Clausius-Clapeyron equation is ... 

The Antoine equation is an empirical relationship between vapor pressure and temperature with three fitted parameters—Aa,Ba,Ca-... 

The free energy change -RT In q> is sometimes used as an approximation to the heat of wetting. For this approximation to be valid, the equilibrium relationship must obey a degenerate Antoine expression... 

In addition to marking the phase boundary, line FC expresses the relationship between saturation pressure and temperature. The saturation pressure generally increases quickly with temperature up to the critical point. There is no vapor-liquid transition above the critical point therefore, the relationship between saturation pressure and temperature exists only below the critical point. The saturation pressure of pure component is an important physical property and a required parameter in many calculations of phase equilibria. Several equations have been developed to describe the mathematical relationship between saturation pressure and temperature. One of the most widely used is the Antoine equation ... 

At the vapor-liquid boundary, a single-phase system splits into two phases,i each with its own properties (molar volume, enthalpy, entropy, etc.). The precise conditions under which phase splitting occurs is an important problem in thermodynamics. Up to this point we have relied on tabulated values and empirical equations, such as the Antoine equation, to establish the relationship between saturation temperature and pressure. In this chapter we develop a connection between the conditions at saturation and the equation of state. The key thermodynamic property that makes this connection possible is the Gibbs energy. 

Applying the Antoine equation (3.30) to the Clausius-Clapeyron equation, the allowable range for the parameter C can be derived. Using Eq. (3.31) and the approximation (3.26), the relationship... 

The relationship between the vapor pressure and the temperature is established by the Antoine equation ... 

Antoine-Laurent Lavoisier, the father of nutrition, recognized the relationship between food and respiration in the l700 s. In 1830, Dutch chemist Gerard Johann Mulder classified proteins. W. O. Atwater, the father of American nutrition, pubfished the first table of food values in 1896. Two decades later, American biochemist E. V. McCollum referred to vitamins and minerals as protective foods. ... 

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