Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 17
Book Description
The Knudsen effusion method was used to measure the vapor pressure of ZrO2 and a stoichiometric ZrO2+Zr mixture between 2014 and 2290 K. The pressure was calculated from rate of effusion data, using the equation p=m square root of 2 pi RT/M (p is the pressure in atmospheres; m, the rate of effusion in g/sq cm/sec; R, the molar gas constant; and M, the mol wt of the vapor). The same rates of evaporation in both cases indicated that ZrO2 vaporizes as ZrO2. The mean heat of evaporation (140.3 + or - 1.5 kcal) of ZrO2 was determined from the slope of the log p vs 1/T plot for the stated temperature range. By using a previously determined heat of evaporation for Zr and delta H sub f of ZrO2(s) (NBS values), 375 + or - 5 kcal/mol was obtained for the heat of dissociation for ZrO2 (g) into Zr (g) and O (g). The bp pf ZrO2 was calculated to be 3735 K from the NBS data for temperature, heat, and entropy of fusion. (See also AD18365).
VAPOR PRESSURES OF INORGANIC SUBSTANCES: ZIRCONIUM DIOXIDE.
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 17
Book Description
The Knudsen effusion method was used to measure the vapor pressure of ZrO2 and a stoichiometric ZrO2+Zr mixture between 2014 and 2290 K. The pressure was calculated from rate of effusion data, using the equation p=m square root of 2 pi RT/M (p is the pressure in atmospheres; m, the rate of effusion in g/sq cm/sec; R, the molar gas constant; and M, the mol wt of the vapor). The same rates of evaporation in both cases indicated that ZrO2 vaporizes as ZrO2. The mean heat of evaporation (140.3 + or - 1.5 kcal) of ZrO2 was determined from the slope of the log p vs 1/T plot for the stated temperature range. By using a previously determined heat of evaporation for Zr and delta H sub f of ZrO2(s) (NBS values), 375 + or - 5 kcal/mol was obtained for the heat of dissociation for ZrO2 (g) into Zr (g) and O (g). The bp pf ZrO2 was calculated to be 3735 K from the NBS data for temperature, heat, and entropy of fusion. (See also AD18365).
Publisher:
ISBN:
Category :
Languages : en
Pages : 17
Book Description
The Knudsen effusion method was used to measure the vapor pressure of ZrO2 and a stoichiometric ZrO2+Zr mixture between 2014 and 2290 K. The pressure was calculated from rate of effusion data, using the equation p=m square root of 2 pi RT/M (p is the pressure in atmospheres; m, the rate of effusion in g/sq cm/sec; R, the molar gas constant; and M, the mol wt of the vapor). The same rates of evaporation in both cases indicated that ZrO2 vaporizes as ZrO2. The mean heat of evaporation (140.3 + or - 1.5 kcal) of ZrO2 was determined from the slope of the log p vs 1/T plot for the stated temperature range. By using a previously determined heat of evaporation for Zr and delta H sub f of ZrO2(s) (NBS values), 375 + or - 5 kcal/mol was obtained for the heat of dissociation for ZrO2 (g) into Zr (g) and O (g). The bp pf ZrO2 was calculated to be 3735 K from the NBS data for temperature, heat, and entropy of fusion. (See also AD18365).
The Free Energies of Vaporization and Vapor Pressures of Inorganic Substances
Author: Kenneth Keith Kelley
Publisher:
ISBN:
Category : Chemistry, Inorganic
Languages : en
Pages : 146
Book Description
Publisher:
ISBN:
Category : Chemistry, Inorganic
Languages : en
Pages : 146
Book Description
Handbook of Vapor Pressure: Volume 4
Author: Carl L. Yaws
Publisher: Gulf Professional Publishing
ISBN: 0080533833
Category : Science
Languages : en
Pages : 375
Book Description
This series provides engineers with vapor pressure data for process design, production, and environmental applications.
Publisher: Gulf Professional Publishing
ISBN: 0080533833
Category : Science
Languages : en
Pages : 375
Book Description
This series provides engineers with vapor pressure data for process design, production, and environmental applications.
Vapor Pressures of Zirconium Tetrachloride and Hafnium Tetrachloride
Author: D. W. Kuhn
Publisher:
ISBN:
Category : Hafnium tetrachloride
Languages : en
Pages : 46
Book Description
Publisher:
ISBN:
Category : Hafnium tetrachloride
Languages : en
Pages : 46
Book Description
Thermophysical Properties of Solid Materials
Author: Armour Research Foundation (U.S.)
Publisher:
ISBN:
Category : Materials
Languages : en
Pages : 434
Book Description
Publisher:
ISBN:
Category : Materials
Languages : en
Pages : 434
Book Description
Vaporization of Zirconium Oxide
Author: M. M. Nakata
Publisher:
ISBN:
Category : Vaporization, Heats of
Languages : en
Pages : 32
Book Description
Publisher:
ISBN:
Category : Vaporization, Heats of
Languages : en
Pages : 32
Book Description
Vapor Pressure of Zirconium Tetrachloride by Molecular Effusion
Author: James M. Scarborough
Publisher:
ISBN:
Category : Vapor pressure
Languages : en
Pages : 32
Book Description
Briefly, the methods of determining low vapor pressures have been reviewed. Emphasis has been placed on molecular effusion, including a theoretical discussion and the subsequent application of molecular beams to the determination of vapor pressure. The problems met in the preparation, purification and handling of anhydrous zirconium tetrachloride have been discussed. Vapor pressure measurements on zirconium tetrachloride have been made over a temperature range of fifty degrees, 70 deg C. to 120 deg C, . and the mean molar heat of sublimation for this temperature range has been calculated. The value of 20.3 kcal per mole obtained is not unreasonable in view of the fact that values for the same quantity determined by other investigators in the temperature range of 239 deg C. to 346 deg C. is reported to be 24.4 kcal. per mole.
Publisher:
ISBN:
Category : Vapor pressure
Languages : en
Pages : 32
Book Description
Briefly, the methods of determining low vapor pressures have been reviewed. Emphasis has been placed on molecular effusion, including a theoretical discussion and the subsequent application of molecular beams to the determination of vapor pressure. The problems met in the preparation, purification and handling of anhydrous zirconium tetrachloride have been discussed. Vapor pressure measurements on zirconium tetrachloride have been made over a temperature range of fifty degrees, 70 deg C. to 120 deg C, . and the mean molar heat of sublimation for this temperature range has been calculated. The value of 20.3 kcal per mole obtained is not unreasonable in view of the fact that values for the same quantity determined by other investigators in the temperature range of 239 deg C. to 346 deg C. is reported to be 24.4 kcal. per mole.
Vapor Pressure of Organic Compounds
Author: Thomas Earl Jordan
Publisher:
ISBN:
Category : Science
Languages : en
Pages : 610
Book Description
Publisher:
ISBN:
Category : Science
Languages : en
Pages : 610
Book Description
Vapor Pressures of Various Compounds at Low Temperatures
Author: G. A. Burrell
Publisher:
ISBN:
Category : Vapor pressure
Languages : en
Pages : 32
Book Description
Publisher:
ISBN:
Category : Vapor pressure
Languages : en
Pages : 32
Book Description