Which term best describes the property that represents how much heat a substance can store per unit mass?

The term that accurately describes the property representing how much heat a substance can store per unit mass is specific heat. Specific heat is defined as the amount of heat required to raise the temperature of one unit mass of a substance by one degree Celsius (or one Kelvin). This property is crucial in thermodynamics and plays a significant role in understanding how different materials respond to heat.

For example, water has a high specific heat capacity, which means it can absorb a considerable amount of heat without a significant change in temperature. This characteristic is important in various applications, including air conditioning and refrigeration, where materials must effectively manage heat transfer.

In contrast, thermal conductivity refers to how well a substance conducts heat, specific gravity is a measure of the density of a substance compared to water, and latent heat pertains to the heat energy required for a phase change in a substance without a change in temperature. These terms address different aspects of thermal properties and do not specifically relate to the capacity of a material to store heat per unit mass.