Singapore: World Scientific Publishing Co. Pte. Ltd.
The reaction of superconducting YBa2Cu3Oy powder with water is studied inetically. The initial rate law is found as Ro = k[S]ao [H3O+]bo where [S]o is the initial surface area of the solid, a and b is found to be 0.94 ± 0.02 and 0.318 ± 0.002, respectively. For 100.7 mg powder with a mean radius of 0.0265 mm at pH 7.00 and 298 K, Ro is 2.21 X 10-4 mol．min-1. Using a = 1 and b = 0.3, the rate constant, k, obtained at 283, 298 and 313 K is 0.64, 1.84 and 4.91 X 10-3 mol．min-1．cm-2．M-0.3, respectively. The activation energy is 50.0 Kj．mol-1 and pre-exponential factor is 1.09 X 106 mol．min-1．cm-2．M-0.3, as calculated from the Arrhenius equation.
International Journal of Modern Physics B 17(18-20), pp.3629-3635