No Follow. Whether raw or cooked, food can be chock-full of dangerous bacteria long before you can smell it. Perishable food (like chicken and other meats) should be tossed if left out at room temperature more than two hours (much less if in a warm room).
A catalytic converter is a simple device that uses basic redox reactions to reduce the pollutants a car makes. It converts around 98% of the harmful fumes produced by a car engine into less harmful gases. It is composed of a metal housing with a ceramic honeycomb-like interior with insulating layers.
If an engine is running well, there isn't really much for  the catalytic converter to do. If the engine is in need of a  tune-up, the catalytic converter may get quite a workout and in the  process it can get very hot. Also, deposits can build up on a  catalytic converter, making it useless.