Kinetics and mechanism of alkaline hydrolysis of urea and sodium cyanate
نویسنده
چکیده
The variation of k10bs with [alkali] is linear. at [OH-]=5.0 to 1.5 mol dm-3, thereafter a sharp increase in the reaction rate is observed for first step hydrolysis of urea. The second step rate constant (k2obS)is found to be independent of [alkali].Hydrolysis of urea in alkaline medium follows an eleminationaddition mechanism. The reaction does not proceed through the formation and decomposition of tetrahedral intermediate. Sodium cyanate hydrolysis obeys an irreversible pseudo-first order kinetics. [OH-] has no significant effect on the rate constants. The following rate equations have been derived for the two step hydrolysis of urea.
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تاریخ انتشار 2017