For there to a measurable amount of heat, there must be a change in in the system. a. Enthalpy
b. Temperature
c. Mass
d. Rate

b.temperature

in a calorimetric determination, either 1. an exothermic process occurs and heat, q, is negative, indicating that thermal energy is transferred from the system to its surroundings, or 2. an endothermic process occurs and heat, q, is positive, indicating that thermal energy is transferred from the surroundings to the system.