The heat of a reaction can be predicted and understanding Constanta, Hess's law, Experimental

Heat generated by a chemical reaction need not be derived from several reactions, including data relating to compounds and by using constant heat summation using Hess law. Without experimental data, the heat from a chemical reaction can be obtained by using quantum chemistry calculations.

Constants are variables that have fixed values, once rated the constant variable during the program running constant value will not change. Constants are usually used to store certain values which are fixed like-value of earth gravity, Fi, and constant-constants in physics or other mathematical formula. Pendeklarasian a constant manner similar to variables, constants pendeklarasian research data private and public.

Hess's law is a law in physical chemistry for the expansion of Hess in Hess cycle. This law is used to predict the enthalpy change of the law of conservation of energy (expressed as a state function ΔH).

Experimental is a study in which found at least one variable is manipulated to study the cause-effect relationships.