Chlorine trifluoride shows up on many pop science content, which is how I learned about it just today, as an incredibly reactive compound capable of oxidizing seemingly incombustible substances (glass, concrete, ashes, asbestos). One source explicitly mentions that it is more reactive than fluorine, the strongest oxidizer of all elements.
I got confused when I read that chlorine trifluoride can be produced by heating chlorine and fluoride together. From what I could gather, the reaction is also exothermic. So if I hadn't known that chlorine trifluoride was a nightmare fire chemical, I would've assumed it was more stable than chlorine or fluorine.
I think the confusion might be down to the terms reactivity and stability. Some sources will treat them like antonyms, but some treat them as a kinetic and thermodynamic property, respectively. Is the latter the proper explanation, that chlorine trifluoride is thermodynamically more stable but it takes less energy to break its bonds and react with other chemicals? It sounds reasonable, but I'd like some clarification.