Kinetics and thermochemistry of the sec-C sub 4 H sub 9 + HBr rightleftharpoons n-C sub 4 H sub 10 + Br equilibrium
- Catholic Univ. of America, Washington, DC (USA)
The kinetics of the sec-C{sub 4}H{sub 9} + HBr reaction was studied in a tubular reactor coupled to a photoionization mass spectrometer. The sec-C{sub 4}H{sub 9} radicals were produced homogeneous in the reactor by pulsed UV laser photolysis. Radical decays in the presence of different HBr concentrations were monitored in time-resolved experiments. Rate constants were obtained as a function of temperature (299-533 K). This kinetic information was combined with knowledge of the rate constant of the reverse reaction to obtain both the entropy (343 ({plus minus}9) J mol{sup {minus}1} K{sup {minus}1}) and heat of formation (66.7 ({plus minus}3.0) kJ mol{sup {minus}1}) of the sec-C{sub 4}H{sub 9} radical at 298 K in a second law determination. The secondary C-H bond energy in n-C{sub 4}H{sub 10} derived from this heat of formation is 411 ({plus minus}3) kJ mol{sup {minus}1}. This study also provides a reconciliation of the formerly disparate sec-C{sub 4}H{sub 9} heats of formation that were derived from studies of different kinds of chemical equilibria.
- OSTI ID:
- 6330698
- Journal Information:
- Journal of Physical Chemistry; (USA), Journal Name: Journal of Physical Chemistry; (USA) Vol. 94:19; ISSN JPCHA; ISSN 0022-3654
- Country of Publication:
- United States
- Language:
- English
Similar Records
Kinetics and thermochemistry of the reactions of alkyl radicals (CH sub 3 , C sub 2 H sub 5 , i-C sub 3 H sub 7 , s-C sub 4 H sub 9 , and t-C sub 4 H sub 9 ) with HI: A reconciliation of the alkyl radical heats of formation
Kinetics and thermochemistry of C sub 2 H sub 3 and CH sub 2 CCl radicals: Study of the C sub 2 H sub 3 + HCl = C sub 2 H sub 4 + Cl and CH sub 2 CCl + HCl = C sub 2 H sub 3 Cl + Cl reactions
Related Subjects
400201* -- Chemical & Physicochemical Properties
ALKANES
ALKYL RADICALS
BUTANE
ENTHALPY
ENTROPY
FORMATION HEAT
HYDROBROMIC ACID
HYDROCARBONS
HYDROGEN COMPOUNDS
INORGANIC ACIDS
KINETICS
MASS SPECTROMETERS
MEASURING INSTRUMENTS
MEDIUM TEMPERATURE
ORGANIC COMPOUNDS
PHYSICAL PROPERTIES
RADICALS
REACTION HEAT
REACTION KINETICS
SPECTROMETERS
THERMODYNAMIC PROPERTIES
THERMODYNAMICS