title: [Kinetics of solid-state decomposition of aspirin].
abstract: The kinetics of the solid-state decomposition of aspirin was studied at 85 degrees, 80 degrees, 75 degrees, 70 degrees C and various relative humidities. Decomposition percentage of aspirin (x) and time (t) could be described by the equation: x = ktn where k is a constant which depends on the temperature and relative humidity. The water vapour pressure effected on the solid-state decomposition of aspirin may be presented by the Arrhenius equation: k = A.exp (-E/RT).Ps where T is the absolute temperature, P is water vapour pressure, s is a constant, R is the gas constant, A is another constant, E is the activation energy. From this equation, the activation energy of the decomposition of aspirin is calculated to be 122.17kJ.mol-1 (29.2 kcal.mol-1).
authors.forename: P
authors.initials: P
authors.lastname: He
authors.forename: Q Y
authors.initials: QY
authors.lastname: Gao
authors.forename: G K
authors.initials: GK
authors.lastname: Yin
mesh_terms: D001241:Aspirin; D004355:Drug Stability; D007700:Kinetics
chemical_list: D001241:Aspirin