The combustibility of a substance is an example of what type of property?

Combustibility is classified as a chemical property because it describes a substance's ability to undergo a chemical reaction when exposed to heat or flame. This reaction typically involves the substance reacting with oxygen to produce heat and light, along with new products such as gases and ash. Since combustibility pertains to how a substance transforms into different substances during a chemical reaction, it falls squarely under the umbrella of chemical properties.

In contrast, physical properties refer to characteristics that can be observed without changing the chemical composition of a substance, such as color, melting point, and density. Biological properties would relate more to living organisms and their interactions, which is not applicable here, while mechanical properties pertain to the physical behavior of materials under forces, also not relevant to the concept of combustibility. Thus, identifying combustibility as a chemical property reflects a deeper understanding of how substances interact and change at a molecular level.