What property describes how quickly a material will conduct heat?

Thermal conductivity is the property that specifically describes how quickly a material will conduct heat. It is measured in terms of the rate at which heat flows through a material when there is a temperature difference across that material. Materials with high thermal conductivity, such as metals, allow heat to transfer quickly, making them efficient conductors of heat.

In contrast, materials with low thermal conductivity, like insulators, do not transfer heat well and thereby slow down heat transfer. Understanding thermal conductivity is crucial in applications such as building construction and fire safety, where the movement of heat can significantly affect both structural integrity and occupant safety during a fire incident.

The other properties listed relate to thermal characteristics but do not address the speed of heat conduction directly. For example, thermal resistance refers to the ability of a material to resist heat flow, thermal mass describes the ability of a material to absorb and store heat, and thermal expansion pertains to how materials change size in response to temperature changes. These concepts are important in their own right but are distinct from the concept of thermal conductivity.