$Hg^{2+}$촉매 존재하에서 cis-amminechlorobis(ethylenediamine)cobalt(III)의 Cl이 $H_2O$로 치환되는 반응을 전자흡수 스펙트라로 속도론적 연구를 하였다. 그 결과 $cis-[Co(en)_2(NH_3)Cl]^{2+}$에 대해서 각각 1차인 총괄반응이 2차반응이다. 활성화 파라메타인 ${Delta}H^{ eq}$와 ${Delta}S^{ eq}$는 각각 12.9 kcal/mol, -19.3 e.u 이고 $Hg^{2+}$에 의한 반응속도상수는 $1.65{ imes}10^{-2}l/mol.sec$가 됨을 알았다. 이러한 속도 자료로부터 본 반응계의 Cl이 $H_2O$로 치환되는 반응은 촉매인 $Hg^{2+}$가 관여하는 Id 메카니즘을 제안하였다.
A kinetic study was made to determine the mechanism of the aquation of $cis-[Co(en)_2(NH_3)Cl]^{2+};in;Hg^{2+}$ aqueous solution. The progress of reaction was followed UV/vis-spectrophotometrically by a measurement of the absorbance at a specific wave length (530nm) of $cis-[Co(en)_2(NH_3)Cl]^{2+}$ as a function of time. The experimental results have shown that the reaction rate is dependent upon the concentration of $Hg^{2+}$ that act as a catalyst. And it was found that the overall reaction proceed with second order, first order with respect to Co(III) complex and $Hg^{2+}$. Activation parameters, ${Delta}H^{ eq};and;{Delta}S^{ eq}$, were obtained as 12.9 kcal/mol and -19.3 e.u., respectively. We have proposed a plausible reaction mechanism which is consistent with the observed rate equation.
