What is defined as the amount of heat needed to change the temperature of a substance without changing its state?

The correct choice pertains to the concept of heat required to change the temperature of a substance while keeping it in the same phase. This concept is specifically referred to as sensible heat. Sensible heat is the energy absorbed or released by a substance during a change in temperature but not a change in state.

When you heat a substance, the temperature rises, which indicates that energy is being added as sensible heat. This contrasts with latent heat, which is the energy absorbed or released during a phase change (e.g., melting, boiling) where the temperature remains constant while the substance changes state.

Specific heat, while related, refers to the amount of heat per unit mass required to raise the temperature of a substance by one degree Celsius. Thus, it’s a measure and not the process itself.

Thermal energy refers to the total kinetic energy of the particles in a substance, which includes both the heat content and the energy associated with temperature but does not specifically define the heat needed to change temperature without a state change.

Understanding these distinctions is key in thermodynamics and energy transfer processes.