What compound is formed when overheated oil breaks down?

When oil is overheated, it can undergo a process known as thermal decomposition. This results in a breakdown of the oil's molecular structure, leading to the formation of a variety of byproducts. Coke is one such byproduct that can be formed when hydrocarbon substances—like oil—are subjected to high temperatures in the absence of air. The heating process causes the oil molecules to break apart and recombine into solid, carbon-rich materials.

Coke itself is essentially a porous, carbon-rich solid that is formed from the superheating of organic materials. It is commonly associated with processes in industrial applications, particularly in the production of metals and in other high-temperature chemical processes. Its formation is indicative of the intense thermal breakdown that oil experiences when exposed to excessive heat.

The other compounds mentioned are products of the breakdown of overheated oil as well, but they do not accurately represent the primary solid carbonaceous material formed during this process. For instance, tar and smoke are both associated with incomplete combustion and other degradation processes but do not explicitly capture the concentrated carbon structure that coke represents. Carbon dioxide, while a product of combustion, is not a solid and does not align with the primary focus on the breakdown products of overheated oil. Thus, coke stands out