The hydroxide-assisted hydrolysis of cyanogen chloride in aqueous solution

The hydrolysis of cyanogen chloride (ClCN) was studied as a function of tem perature and pH. Results were used to resolve discrepancies among previousl y reported kinetic constants. The pH dependence was studied over a range of 9.54-10.93 at a temperature of 21.0 degreesC. The effect of temperature wa s investigated over the range of 10-30 degreesC at a pH of approximately 10 . Changes in the concentrations of ClCN and the reaction products cyanic ac id and chloride ion were monitored with time. For the conditions correspond ing to these experiments, the hydroxide-assisted hydrolysis pathway predomi nated. Collision Frequency factor and activation energies recommended to re present the hydrolysis of ClCN in aqueous solution are A = 2.06 x 10(11) M- 1 s(-1) and E-a = 60. 980 J mol(-1) for the hydroxide-ion-assisted reaction , and A = 9.97 x 10(8) s(-1) and E-a = 87.180 J mol(-1) for the water-assis ted reaction, (C) 2001 Elsevier Science Ltd. All rights reserved.