1. Definitions

1.1 Thermal capacities

When a quantity of heat ΔQ is received by a system and causes a temperature change ΔT = T ₁ – T ₂ (with T ₁ and T ₂ , respectively the start and end temperatures of heating), the average heat capacity C of the system of mass m is written :

provided the system undergoes neither reaction nor first-order transition in the Ehrenfest sense (enthalpy and entropy discontinuities) between T ₁ and T _...