In our previous work, the thermokinetic and mechanism of inter conversion of nitro and nitrito isomers of pentaam-minecobalt(III) chloride was investigated by a single heating ratenon-isothermal DSC approach [19]. However, in order to obtain more precise data [35], in this work we attempted to elucidate above-mentioned thermal phenomena using multiple heating ratesmethod. An ASTM E698 method which sometime called kinetictriplet and is independent from reaction kinetic model, was usedto determine the Arrhenius parameters [36]. The activation energy of the reactions was evaluated from Kissinger’s plot of ln(ˇ/T2m)against 1/Tmwhich is given by Eq. (5) [37]: