The Equilibrium and the Determination of D00 (H—CN)

1975 ◽  
Vol 53 (16) ◽  
pp. 2365-2370 ◽  
Author(s):  
Don Betowski ◽  
Gervase Mackay ◽  
John Payzant ◽  
Diethard Bohme
Keyword(s):  
Free Energy ◽  
Standard Enthalpy ◽  
Transfer Reaction ◽  
Standard Free Energy ◽  
Proton Transfer Reaction ◽  
Enthalpy Change ◽  
Standard Free Energy Change ◽  
Flowing Afterglow ◽  
Standard Enthalpy Change

The rate constants and equilibrium constant for the proton transfer reaction [Formula: see text] have been measured at 296 ± 2 K using the flowing afterglow technique: kforward = (2.9 ± 0.6) × 10−9 cm3molecule−1s−1, kreverse = (1.8 ± 0.4) × 10−10 cm3 molecule1 s−1, and K = 16 ± 2. The measured value of K corresponds to a standard free energy change, ΔG296°, of −1.6 ± 0.1 kcal mol−1 which provides values for the standard enthalpy change, ΔH298°= −1.0 ± 0.2 kcal mol−1, the bond dissociation energy, D00(H—CN) = 124 ± 2 kcal mol−1, and the proton affinity, p.a.(CN−) = 350 ± 1 kcal mol−1.

Adsorption of Liquids and Swelling of Wood IV. Temperature Dependence on the Adsorption

Holzforschung ◽  
1999 ◽  
Vol 53 (6) ◽  
pp. 669-674 ◽  
Author(s):  
Kei Morisato ◽  
Hitoshi Kotani ◽  
Yutaka Ishimaru ◽  
Hiroyuki Urakami
Keyword(s):  
Free Energy ◽  
Temperature Dependence ◽  
Standard Enthalpy ◽  
Cell Walls ◽  
Standard Free Energy ◽  
Isosteric Heat ◽  
Enthalpy Change ◽  
Standard Free Energy Change ◽  
Standard Enthalpy Change ◽  
Low Activity

Summary For the purpose of understanding the swelling phenomenon of wood in liquids, the contributions of enthalpic and entropic terms to the standard free energy change of adsorption have been determined by measuring the temperature dependence of adsorption isotherms. The values of standard enthalpy change of adsorption are smaller for alcohols having both proton-accepting and -donating properties than for acetone having only a proton-accepting property. The results are discussed in terms of the proton-accepting power and the cohesive energy of the respective adsorbate liquids. Methanol showed a larger isosteric heat of adsorption to dried wood than to pre-swollen wood, and the amounts of methanol and acetone adsorbed on dried wood exceeded those on swollen wood within the low activity range. These results indicate the presence of more exothermic sites in dried wood than in pre-swollen wood, and of pre-existing spaces and/or parts loosely hydrogen-bonded between wood constituents in the cell walls of dried wood.

scholarly journals A method for investigating the effect of temperature on the 695 nm band of insoluble cytochrome c

1975 ◽  
Vol 149 (1) ◽  
pp. 169-177 ◽  
Author(s):  
T A Moore ◽  
C Greenwood
Keyword(s):  
Ionic Strength ◽  
Cytochrome C ◽  
Computer Analysis ◽  
Standard Enthalpy ◽  
Entropy Change ◽  
Enthalpy Change ◽  
Effect Of Temperature ◽  
Standard Entropy ◽  
Ferricytochrome C ◽  
Standard Enthalpy Change

A method is described for computer analysis of simple spectrophotometric changes in particulate systems, and this has been applied to the bleaching of the 695 nm band of insoluble ferricytochrome c by temperature. The results show that insolubilization has no effect on the standard enthalpy change but lowers the value for the standard entropy change. This effect appears to be independent of the concentration of the gel matrix to which the cytochrome c is bound, but dependent on the ionic strength of the surrounding solution.

High Temperature Electrochemical Determination of the Thermodynamic Stability of the Iron-Rich, Iron-Niobium Intermetallic Phase

1969 ◽  
Vol 24 (10) ◽  
pp. 1580-1585 ◽  
Author(s):  
Giovanni B. Barbi
Keyword(s):  
Free Energy ◽  
Intermetallic Phase ◽  
Standard Free Energy ◽  
Chemical Oxidation ◽  
Electrochemical Determination ◽  
Electrolytic Cell ◽  
Galvanic Cells ◽  
Free Energy Of Formation ◽  
Energy Of Formation

Abstract A non-stationary technique of e.m.f. measurements after polarization of solid galvanic cells, previously applied to the determination of the standard free energy of formation of metal oxides, has been extended to intermetallic phases. The chief condition of applicability of this technique to intermetallic compounds is that the rates of recombination of the cathodic reduction products to yield the stable intermetallic phase be high as compared with that of chemical oxidation at the interface with the solid intermediate electrolyte, due to oxygen impurities in the gas phase. In particular, the solid electrolytic cell:(y values expressing the ε-phase iron-rich boundary compositions according to different authors investigations) was examined.Values of the standard free energy of formation of Fe7-yNb2 from the elements, ranging between-3.77+0.72-10-3 T and -5.66+1.09 · 10-3 T kcal/atom were found.

scholarly journals Correction: The applicability of proton transfer reaction-mass spectrometry (PTR-MS) for determination of isocyanic acid (ICA) in work room atmospheres

2018 ◽  
Vol 20 (2) ◽  
pp. 415-415
Author(s):  
Mikolaj Jan Jankowski ◽  
Raymond Olsen ◽  
Claus Jørgen Nielsen ◽  
Yngvar Thomassen ◽  
Paal Molander
Keyword(s):  
Mass Spectrometry ◽  
Proton Transfer ◽  
Transfer Reaction ◽  
Proton Transfer Reaction ◽  
Reaction Mass ◽  
Isocyanic Acid

Correction for ‘The applicability of proton transfer reaction-mass spectrometry (PTR-MS) for determination of isocyanic acid (ICA) in work room atmospheres’ by Mikolaj Jan Jankowski et al., Environ. Sci.: Processes Impacts, 2014, 16, 2423–2431.

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