K calculating

Equilibrium constants,, for all possible dimerization reactions are calculated from the metastable, bound, and chemical contributions to the second virial coefficients, B , as given by Equations (6) and (7). The equilibrium constants, K calculated using Equation (3-15). 

The nitrogen adsorption isotherm is determined for a finely divided, nonporous solid. It is found that at = 0.5, P/P is 0.05 at 77 K, gnd P/F is 0.2 at 90 K. Calculate the isosteric heat of adsorption, and AS and AC for adsorption at 77 K. Write the statement of the process to which your calculated quantities correspond. Explain whether the state of the adsorbed N2 appears to be more nearly gaslike or liquidlike. The normal boiling point of N2 is 77 K, and its heat of vaporization is 1.35 kcal/mol. 

Effect of a Constant Determinate Error on the Value of k Calculated Using a Single-Point Standardization... 

If the data follow the kinetic scheme presented here, the values of k, calculated for the different runs should be constant ... 

The temperature dependences of k, calculated by Hancock et al. [1989], are given in fig. 48. The crossover temperature equals 25-30 K. The weak increase of k T) with decreasing temperature below is an artefact caused by extending the gas-phase theory prefactor to low temperatures without taking into account the zero-point vibrations of the H atom in the crystal. For the same reason the values of the constants differ by 1-2 orders of magnitude from the experimental ones. 

Values of K calculated from C, agree within 10% of published data of... 

I = complex impedance, B = conductivity bridge, C = capillary viscometer, P = pycnometer or dilatometer, V = volumetric glassware, I = instrument, U = method unknown (not provided in the reference). Conductivity at 298 K calculated from VTF parameters given in reference. Binary composition of 42.0-58.0 mol % [(CH3)3S]Br-HBr. 

K is 0.64 at 900 K. Calculate the equilibrium partial pressures of all species, starting with... 

E6.12 The HC1 pressure in equilibrium with a 1.20 molal solution is 5.15 x 10 8 MPa and the mean ionic activity coefficient is known from emf measurements to be 0.842 at T = 298.15 K. Calculate the mean ionic activity coefficients of HC1 in the following solutions from the given HC1 pressures... 

Values of diffusion-controlled rate constants at 298 K calculated for different solvents according to Eq. (9-13)... 

To examine the shape that this equation enables us to predict for log k or AG as a function of AG, we substitute the parameter for a specific case. The value of kfc will be taken as 7.4 x 109 L mol-1 s l, that being the value in water at 298 K. Values of k calculated from Eq. (10-66) are shown in Fig. 10-10 as a function of AG. Values of AG are also depicted. The value A = 80 kJ mor1 was used and Z was taken from TST as 6.21 x 1012 s l at 298 K. The effect of introducing the diffusion-controlled limit is that the plot is shaped like a truncated parabola. This figure was drawn with K = k /k-Ac = 0.2 L mol-1. The left side of each of the diagrams shows the inverted region where k decreases and AG increases as AG becomes more negative. 

A large thermoplastic sheet, 10 mm thick, at an initial temperature of 20 C (293 K). is to be heated in art oven in order to enable it to be moulded. The oven temperature is maintained at 100°C (373 K), the maximum temperature to which the plastic may be subjected, and it is necessary to ensure that the temperature throughout the whole of the sheet reaches a minimum of 80 °C (353 K). Calculate the minimum length of time for which the sheet must be heated. 

A twin-cylinder, single-acting compressor, working at 5 Hz, delivers air at 515 kN/m2 pressure, at fee rate of 0.2 m3/s. If the diameter of the cylinder is 20 cm, the cylinder clearance ratio 5% and the temperature of the inlet air 283 K, calculate the length of stroke of the piston and the delivery temperature. 

A metal pipe of 12 mm outer diameter is maintained at 420 K. Calculate the rate of heat loss per metre run in surroundings uniformly at 290 K, (a) when the pipe is covered with 12 mm thickness of a material of thermal conductivity 0.35 W/m K and surface emissivity 0.95, and (b) when the thickness of the covering material is reduced to 6 min. but the outer surface is treated so as to reduce its emissivity to 0.10. 

A batch of reactants of specific heat 3.8 kJ/kg K and of mass 1000 kg is heated by means of a submerged slearn coil of area 1 m2 fed with steam at 390 K. If the overall heat transfer coefficient is 600 W/m2 K, calculate the time taken to heat the material from 290 to 360 K, if heat losses to the surroundings are neglected. 

A longitudinal tin on the outside of a circular pipe is 75 mm deep and 3 mm thick. If tire pipe surface is at 400 K. calculate the heat dissipated per metre length from the fin to the atmosphere at 290 K if the coefficient of heat transfer from its surface may be assumed constant at 5 W/m2 K, The thermal conductivity of the material of the fin is 50 W/m K and the heat loss from the extreme edge of the fin may be neglected. It should be assumed that the temperature is uniformly 400 K at the base of the fin. 

NH,(g) at 500. K, calculate whether more ammonia will tend to form when a mixture of composition 2.23 mmol-L 1 N2,... 

The mean value of k calculated from the four experiments is 12 L3-mol 3-s. ... 

Fig. 6b.—Contour diagram of D/k (calculated one-electron bond energy divided by a constant) for s-p-d hybridization.

K(,(., calculated from the octanol-water coefficient (K w) solubility, and melting point data ranged from 2.93 to 3.47, and compared favorably with literature values (Karickhoff 1981). McLean et al. (1988) estimated a lower Kq . of 39, equal to a log of 1.59. More recently, a of 5,100, equal to log 3.7, has been reported (HSDB 1999). These values indicate that methyl parathion is moderately mobile to immobile in soil (Swann et al. 1983). 

Mannhold, R., Dross, K. Calculation procedures for molecular lipophilicity a comparative study. Quant. Struct.-Act. Relat. 1996, 15, 403 09. 

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