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  • Chemistry  (33)
  • 1
    Electronic Resource
    Electronic Resource
    The pyrolysis of acetylene-styrene mixtures between 450 and 550°C (1987)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 19 (1987), S. 659-678 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The pyrolysis of acetylene-styrene mixtures has been studied from 450-550°C in a quartz reaction vessel in the absence and presence of O2 or NO. The rates of disappearance of reactants and formation of adducts are first-order in each reactant. The major product is polymer, with the adducts accounting for about 2.5% and 6.2% of the styrene removed at 450 and 550°C, respectively. The acetylene-to-styrene removal ratio is about 27 independent of temperature. The adducts formed are methyl indene and 1,2-dihydronaphthalene. These are about half-suppressed in the presence of O2 or NO. The rate coefficients for reactant removal and adduct formation are: \documentclass{article}\pagestyle{empty}\begin{document}$$ \log \{ k\{ {\rm C}_{\rm 2} {\rm H}_{\rm 2} \},M^{ - 1} {\rm s}^{ - 1} \} = 7.53 \pm 0.10 - (90.6 \pm 1.5)/2.3RT $$\end{document} \documentclass{article}\pagestyle{empty}\begin{document}$$ \log \{ k\{ {\rm C}_{\rm 8} {\rm H}_{\rm 8} \},M^{ - 1} {\rm s}^{ - 1} \} = 6.63 \pm 0.60 - (98.5 \pm 8.8)/2.3{\rm }\,RT $$\end{document} \documentclass{article}\pagestyle{empty}\begin{document}$$ \log \{ k\{ {\rm C}_{{\rm 10}} {\rm H}_{{\rm 10}} \},M^{ - 1} {\rm s}^{ - 1} \} = 8.27 \pm 0.66 - (143.3 \pm 9.8)/2.3RT $$\end{document} where the activation energies are in kJ/mol and the uncertainties are one standard deviation. As the reaction proceeds, the methyl indene and 1,2-dihydronaphthalene decompose, and indene and naphthalene are formed. In addition, an unidentified isomer of naphthalene is produced as an initial minor product, and it also decomposes as the reaction proceeds.
    Additional Material: 11 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550190708
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  • 2
    Electronic Resource
    Electronic Resource
    Pyrolysis of Propyne/2-Methylbut-1-ene-3-yne mixtures between 350 and 450°C (1989)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 21 (1989), S. 175-191 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: 2-Methylbut-1-ene-3-yne and Propyne mixtures were pyrolyzed at 350-450°C in the absence and presence of O2 and NO. The major product of the reaction is a polymer, but m-xylene and p-xylene are also produced and were studied as the species of interest. The C8H10 formation rate is first-order in C3H4 and C5H6. The rate coefficient is best fitted by \documentclass{article}\pagestyle{empty}\begin{document}$$\log [k({\rm C}_{\rm 8} {\rm H}_{{\rm 10}}),M^{ - 1} s^{ - 1}] = (11.2 \pm 1.0) - (166 \pm 13)/2.3RT$$\end{document} though it is not inconsistent with \documentclass{article}\pagestyle{empty}\begin{document}$$\log [k({\rm C}_{\rm 8} {\rm H}_{{\rm 10}}),M^{ - 1} s^{ - 1}] = (8.17) - (125.9)/2.3RT$$\end{document} where R is the ideal gas constant in kJ/mol-K. Experiments in the presence of NO show that m-xylene and p-xylene formation occur by two processes: a concerted molecular mechanism (≃ 41%) and a singlet diradical mechanism (≃ 59%).
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550210304
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  • 3
    Electronic Resource
    Electronic Resource
    Reactions of ozone with olefins: Ethylene, allene, 1,3-butadiene, and trans- 1,3-pentadiene (1984)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 16 (1984), S. 1227-1246 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The reactions of O3 with ethylene, allene, 1,3-butadiene, and trans-1,3-pentadiene have been studied in the presence of excess O2 over the temperature range 232 to 298 K. The initial O3 pressure was varied from 4-18 mtorr, and the olefin pressure was varied from 0.1 to 4.5 torr (ethylene), 2.8 to 39.6 torr (allene), 52.7 to 600 mtorr (1,3-butadiene) or 26.2 to 106 mtorr (trans-1,3-pentadiene). The O3 decay was monitored by ultraviolet absorption. The reactions are first order in both O3 and olefin, and the rate coefficients are independent of the O2 pressure. For the O3-ethylene system, various diluent gases (O2, N2, air) were used and the rate coefficients were found to be independent of the nature of the diluent gas. The various rate coefficients fit the Arrhenius expressions (k in cm3 s-1): \documentclass{article}\pagestyle{empty}\begin{document}$$\begin{array}{l}{\rm For C}_{\rm 2} {\rm H}_4 :k\{ 232 - 298{\rm K}\} {\rm } = {\rm }(7.72 \pm 0.89){\rm } \times {\rm 10}^{ - 15} \exp [- 5080{\rm } \pm {\rm }60)/RT] \\ {\rm For C}_{\rm 3} {\rm H}_4 :k\{ 252 - 298{\rm K}\} {\rm } = {\rm }(1.54 \pm 0.25){\rm } \times {\rm 10}^{ - 15} \exp [- 5343{\rm } \pm {\rm }87)/RT] \\ {\rm For 1,3 - C}_{\rm 4} {\rm H}_{\rm 6} :k\{ 254 - 299{\rm K}\} {\rm } = {\rm }(2.20 \pm 0.44){\rm } \times {\rm 10}^{ - 14} \exp [- 4828{\rm } \pm {\rm }109)/RT] \\ {\rm For trans - 1,3 - C}_{\rm 5} {\rm H}_{\rm 8} :k\{ 238 - 298{\rm K}\} {\rm } = {\rm }(1.07 \pm 0.25){\rm } \times {\rm 10}^{ - 13} \exp [- 4608{\rm } \pm {\rm }122)/RT] \\ \end{array}$$\end{document} where the reported uncertainties are one standard deviation and R is in cal/mol K.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550161006
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  • 4
    Electronic Resource
    Electronic Resource
    Reactions of alkoxy radicals with O2. III. i-C4H9O radicals (1985)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 17 (1985), S. 503-524 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: i-C4H9ONO was photolyzed with 366-nm radiation at -8, 23, 55, 88, and 120°C in a static system in the presence of NO, O2, and N2. The quantum yield of i-C3H7CHO, Φ{i-C3H7CHO}, was measured as a function of reaction of reaction conditions. The primary photochemical act is and it proceeds with a quantum yield φ1 = 0.24 ± 0.02 independent of temperature. The i-C4H9O radicals can react with NO by two routes The i-C4H9O radical can decompose via or react with O2 via Values of k4/k2 ≃ k4b/k2 were determined to be (2.8 ± 0.6) × 1014, (1.7 ± 0.2) × 1015, and (3.5 ± 1.3) × 1015 molec/cm3 at 23 55, and 88°C, respectively, at 150-torr total pressure of N2. Values of k6/k2 were determined from -8 to 120°C. They fit the Arrhenius expression: \documentclass{article}\pagestyle{empty}\begin{document}$$ \log (k_6 /k_2) = - 2.15 \pm 0.22 - (836 \pm 159)/2.303{\rm T} $$\end{document} For k2 ≃ 4.4 × 1011 cm3/s, k6 becomes (3.2 ± 2.0) × 10-13 exp{-(836 ± 159)/T} cm3/s. The reaction scheme also provides k4b/k6 = 3.59 × 1018 and 5.17 × 1018 molec/cm3 at 55 and 88°C, respectively, and k8b/k8 = 0.66 ± 0.12 independent of temperature, where
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550170504
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  • 5
    Electronic Resource
    Electronic Resource
    Primary photochemical processes in the photolysis of alkyl nitrites at 366 NM and 23°c in the presence of 15NO (1985)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 17 (1985), S. 535-546 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The alkyl nitrites, C2H5ONO, n-C3H7ONO, n-C4H9ONO, and i-C4H9ONO were photolyzed at 23°C in the presence of 15NO at 366-nm incident radiation. The quantum yields of the corresponding isotopically-enriched alkyl nitrites were measured by mass spectrometry. The results indicated that only part of the absorption leads to photodecomposition. The remainder forms an electronically excited state which isotopically exchanges with 15NO. The indicated reactions of the electronically excited state RONO*, are where k3/k2 = 0.50 ± 0.10, 0.62 ± 0.20, 0.42 ± 0.06, and 0.24 ± 0.03 torr, and that k2a/k2 = 1.0, 1.0, 0.64 ± 0.04, and 0.56 ± 0.03, respectively, for C2H5ONO, n-C3H7ONO, n-C4H9ONO, and i-C4H9ONO.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550170506
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  • 6
    Electronic Resource
    Electronic Resource
    The photolysis of N2O at 1470 Å (1971)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 3 (1971), S. 269-282 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The photolysis of pure N2O, N2O and N2, and N2O and C3H6 mixtures at 1470 Å and room temperature has been studied to determine the relative importance of the primary processes. The results are where φ{O(1D)} = 0.515 represents both the O(1D) produced in the primary act and that produced by collisional quenching of O(1S); φ{N2(3Σ)} = 0.084 represents only that portion of N2(3φ) which dissociates N2O on deactivation; and φ{O(1S)} = 0.38 - ±{N(2D)} represents only that portion of O(1S) which enters into chemical reaction with N2O. If the reaction of O(1S) with N2O yields only N2 and O2 as products, which seems likely from potential-energy curve considerations then ±{O(1S)} = 0.135 ± 0.06 and φ{N(2D)} = 0.245 ± 0.06. Young and coworkers [4] have found from spectroscopic observations that the total quantum yield of O(1S) is about 0.5. Thus it can be concluded that collisional removal of O(1S) by N2O yields mainly O(1D) with chemical reaction being less important. Furthermore, most of the O(1D) is produced this way, and the true primary yield of O(1D) is about 0.15. The metastable N(2D) is not deactivated by N2O, but is removed by chemical reaction to produce N2 and NO. The results further indicate that N2(3Σ) dissociates N2O at least 80% of the time during quenching. The relative efficiency of N2O compared to N2 is about 2 for the removal of O(1D). O(1S) is removed about 90 times as efficiently by C3H6 as by N2O.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550030307
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  • 7
    Electronic Resource
    Electronic Resource
    The reactions of O(1D) with ozone and nitrous oxide (1971)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 3 (1971), S. 501-508 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Ozone was photolyzed at room temperature in the presence of N2O at 2537 Å and 2288 Å to produce O(1D) atoms. These atoms can react with either O3 or N2O via From the quantum yield of N2, the relative rate constants k6a/k6 and k2/k6 could be obtained, where k6 + k6a + k6b. The former rate constant ratio was found to be 0.37 ± 0.03 at 2537 Å and 0.33 ± 0.03 at 2288 Å, in good agreement with an earlier report from our laboratory. The ratio k2/k6 was found to be 2.6 at 2537 Å, but 4.1 at 2288 Å. The difference in the two numbers, if real, may reflect differences in reactivity due to different amounts of excess translational energy in the O(1D) atom at the two wavelengths.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550030604
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  • 8
    Electronic Resource
    Electronic Resource
    The photolysis of N2O at 2139 Å and 1849 Å (1972)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 4 (1972), S. 497-512 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The method of chemical difference was utilized to accurately determine the relative importance of all the reaction steps in the direct photolysis of N2O at 2139 Å (25° and 250°C) and 1849 Å (25° C), as well as in the Hg6(1P1)-sensitized photolysis of N2O at 1849 Å (25°C). In all cases, the primary process is predominantly, if not exclusively, \documentclass{article}\pagestyle{empty}\begin{document}$$\begin{array}{*{20}c} {{\rm (1)}} & {{\rm N}_{\rm 2} {\rm O} + hv{\rm or H}_{\rm g} 6(^1 P_1) \to {\rm N}_{\rm 2} + {\rm O(}^{\rm 1} D{\rm)}} \\\end{array}$$\end{document} Experiments with trace amounts of C3H6 added showed a slight, but not significant, difference in product ratios (N2 and O2). From these experiments the quantum yield of O(3P) from all possible sources was estimated as 0.02 ± 0.02. Experiments with excess N2 at 1849 Å indicated that O(1S) was not produced in the direct photolysis. The O(1S) yield is probably zero, and certainly 〈0.05. The O(1D) atom can react with N2O via \documentclass{article}\pagestyle{empty}\begin{document}$$\begin{array}{l} \begin{array}{*{20}c} {{\rm (2)}} & {{\rm O(}^{\rm 1} D{\rm)} + {\rm N}_{\rm 2} {\rm O} \to {\rm N}_{\rm 2} + {\rm O}_2 } \\\end{array} \\ \begin{array}{*{20}c} {{\rm (3)}} & {{\rm O(}^{\rm 1} D{\rm)} + {\rm N}_{\rm 2} {\rm O} \to 2{\rm NO}} \\\end{array} \\ \end{array}$$\end{document} The ratio k2/k3 was found to be 0.69 ± 0.05 in all cases. When combined with other data from our laboratory, the average value is 0.65 ± 0.07. This represents the value for translationally energetic O(1D) atoms. When excess He was added to remove the excess translational energy, k2/k3 rose to 0.83 ± 0.06, which is in reasonable agreement with the value of 1.01 ± 0.06 found in another laboratory. We conclude that for O(1D) atoms with no excess thermal energy, k2/k3 = 0.90 ± 0.10.
    Additional Material: 4 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550040504
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  • 9
    Electronic Resource
    Electronic Resource
    The reaction of O(1D) with H2O and the reaction of OH with C3H6 (1973)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 5 (1973), S. 231-241 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: N2O was photolyzed at 2139 Å to produce O(1D) atoms in the presence of H2O and CO. The O(1D) atoms react with H2O to produce HO radicals, as measured by CO2 production from the reaction of OH with CO. The relative importance of the various possible O(1D )-H2O reactions is The relative rate constant for O(1D) removal by H2O compared to that by N2O is 2.1, in good agreement with that found earlier in our laboratory. In the presence Of C3H6, the OH can be removed by reaction with either CO or C3H6: From the CO2 yield, k3/k2 = 75,0 at 100°C and 55.0 at 200°C to within ± 10%. When these values are combined with the value of k2 = 7.0 × 10-13exp (-1100/RT) cm3/sec, k3 = 1.36 × 10-11 exp (-100/RT) cm3/sec. At 25°C, k3 extrapolates to 1.1 × 10-11 cm3/sec.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550050206
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  • 10
    Electronic Resource
    Electronic Resource
    The oxidation of CFClCFCl and CF2CCl2 (1975)
    New York, NY : Wiley-Blackwell
    International Journal of Chemical Kinetics 7 (1975), S. 399-415 
    Details
    ISSN: 0538-8066
    Keywords: Chemistry ; Physical Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The oxidation of CFClCFCl and CF2CCl2 were studied at room temperature by chlorine- and oxygen-atom initiation. The chlorine-atom initiated oxidation of CFClCFCl yields CCl2FCF(O) as the exclusive product. Its quantum yield is ∼420, which gives k3a/k3b=210 where reactions (3a) and (3b) are The O(3P)—CFClCFCl reaction gives CClFO with a quantum yield of 0.80, polymer, and small amounts of an unidentified product which is probably cyclo-(CFCl)3. Thereaction paths are with k9a/k9=0.80. The overall reaction of O(3P) with CFClCFCl proceed one fifth as fast as the O(3P)-C2F4 reaction. When O2 is also present, the same free-radical chain oxidation occurs by O(3P)initiation as by chlorine-atom initiation.The chlorine-atom initiated oxidation of CF2CCl2 gives CF2ClCCl(O) as the major product, with quantum yields ranging from 42 to 85. Smaller amounts of CF2O and CCl2O are produced in equal amounts with quantum yields of ∼3.5. The reactions responsible for the products are The O(3P)-CF2CCl2interaction yields CF2O and with quantum yields of 1.0 and ∼0.85, respectively. In thepresence of O2 the radical chain products are observed, but the mechanism is different than that for other chloroolefins.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/kin.550070308
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