Mole fractions, calculation

TRUE VAPOR-PHASE MOLE FRACTION. CALCULATED WHEN THE CHEMICAL THEORY IS USED. 

Equilibrium mole fractions calculated using method of Example 7.13. These results are calculated for interest only. They are not needed for the main calculation. The code is specific to initial conditions G = Kthermo PO/P... 

It is desired to separate a binary mixture by simple distillation. If the feed mixture has a composition of 0.5 mole fraction, calculate the fraction which it is necessary to vaporise in order to obtain ... 

Moreover, the objective function obtained by minimizing the square of the difference between the mole fractions calculated by UNIQUAC model and the experimental data. Furthermore, he UNIQUAC structural parameters r and q were carried out from group contribution data that has been previously reported [14-15], The values of r and q used in the UNIQUAC equation are presented in table 4. The goodness of fit, between the observed and calculated mole fractions, was calculated in terms RMSD [1], The RMSD values were calculated according to the equation of percentage root mean square deviations (RMSD%) ... 

The (able below contains solubility and density data lor the salts Na SQ4 and MgS()4. Express their solubilities in terms of molar concentrations, molalities and mole fractions. Calculate the contractions in volume that occur when the solutions are made from the solid salts and the solvent. Comment on the results in terms of the ell ect of ionic charges. The concentrations have been cho-.cn to be comparable. 

Table III. Optimum Values of a12 in the Positive and Negative Regions Based on Ternary Vapor Mole Fraction Calculation...

Example 5.1 A benzene-toluene mixture consists of 50 moles of benzene and 50 moles of toluene. It is desired to reduca the residual benzene concentration to 0.1 mole fraction. Calculate the overall material balance for this distillation. 

Most of the problems at the end of this chapter and Chapter 9 look very much like the problems in Chapters 4 to 6 given values of some process variables (feed and product stream temperatures, pressures, phases, amounts or flow rates, and component mole fractions), calculate values of other process variables. Starting in this chapter, you will also be asked to calculate the heat transferred to or from the process system (one additional variable), which will require writing and solving an energy balance (one additional equation). 

We can use this relationship to check mole fraction calculations or to find a remaining mole fraction if we know all the others. 

A handbook Usts the value of the Henry s Law constant as 3.02 X 10 atm for ethane, C2H15, dissolved in water at 25°C. The absence of concentration units on k means that the constant is meant to be used with concentration expressed as a mole fraction. Calculate the mole fraction of ethane in water at an ethane pressure of 0.15 atm. 

Solution of Equation 9 requires values for x and n as f(r). Since these are not known precisely at any r, values must be guessed and an integration of Equation 16 performed across the cell. In practice initial guesses were made at both sides of the meniscus. Numerical integration was performed across the entire cell, followed by a mass balance. Since the total sample is visible in the schlieren picture, the average mole fraction calculated must match that of the sample as inserted. 

Substitute the mole fraction calculated above and the vapor pressure of the pure solvent into Equation (12.4) to calculate the vapor pressure of each component of the solution. 

Substituting inPtotai and the mole fractions calculated gives 331nuuHg = 0.3429PX +0.657 IPb... 

To calculate the masses of the liquids injected it is necessary to know the densities of the liquids at the temperature and pressure in the injectors. The injectors are not thermostatted but set above the bath in an air-conditioned room. Because the injectors themselves have a large heat capacity, rapid fluctuations in the room temperature will not have a major effect. Long-term drifts in the temperature would be more serious. Compression of the liquids to 500 kPa will cause an increase in density of about 0.05 per cent. Van Ness points out that there will be a negligible error in the mole fraction calculated from atmospheric data provided all volume measurements on both liquids are made at the same applied pressure and the liquids have similar isothermal compressibilities. When the isothermal compressibilities of the two components differ appreciably a more detailed calculation is necessary to determine the mole fraction. 

Here, division by iCiJc, + is needed because the mole fractions calculated directly from ea. rio.27l will... 

Fig. 14.6 Partition coefficient based on mole fractions calculated from measured phase equilibrium compositions at 313, 323, and 333 K, respectively.

Figure 2.1 gives a comparison between the steady state solution for the liquid and the vapour phase mole fractions calculated by the Wavelet-Galerkin method and by a full discrete model. As expected the composition profiles are almost identical, the deviations are resulting from the interpolation of the physical property routines due to the formulation (2.20) of the phase equilibrium coefficient in the wavelet flash. Note that this is no error but merely a... 

Converting concentration units Given the molality of a solution, calculate the mole fractions of solute and solvent and given the mole fractions, calculate the molality (EXAMPLES 12.5 AND 12.6). Given the density, calculate the molarity from the molality, and vice versa (EXAMPLES 12.7 AND 123). 

Mole fraction, calculated from the corresponding chemical shifts x... 

---