Heating of an organic substance to its autoignition temperature is known as which term?

• A. Spontaneous heating
• B. Catalytic heating
• C. Ignition
• D. Pyrolysis

Answer: (A)

This tests understanding of self-heating leading to ignition. When some organic materials oxidize slowly inside the material or in a pile, they generate heat on their own. If that internally produced heat isn’t dissipated, the temperature rises until it reaches the material’s autoignition temperature, meaning it will ignite without an external flame or spark. This process is described as spontaneous heating. It’s different from ignition itself (the moment the material catches fire), from pyrolysis (thermal decomposition that may produce flammable gases but isn’t the self-heating to ignition), and from catalytic heating (heat produced or accelerated by a catalyst). Everyday examples include oily rags or piled materials where heat buildup can lead to spontaneous ignition if not ventilated or spread out.