In order to investigate relative reactivity of dif- ferent oxidants in solid-state reactions of pyrotechnic mixtures, thermal properties of Sn ? Sr(NO3 ) 2 ,Sn ? Ba(NO3 ) 2 , and Sn ? KNO3 pyrotechnic systems have been studied by means of TG, DTA, and DSC methods and the results compared with those of pure oxidants. The apparent # # # activation energy ( E ), DG , DH , and DS of the combustion processes were obtained from the DSC experiments. The results showed that the nature of oxidant has a significant effect on ignition temperature, and the kinetic of the pyro- technic mixtures’ reactions, and the relative reactivity of these mixtures was found to obey in the following order: Sn ? Sr(NO3 ) 2 [ Sn ? Ba(NO3 ) 2 [ Sn ? KNO3 .