Hess Law (20 Min) - target equation, sum of enthalpy, enthalpy of reaction 

Hess law states that if a target chemical equation is equal to the sum of equation 1, equation 2 and equation 3, etc.. then the heat of equation 1, equation 2 and equation 3 are also going to add up to a sum of the enthalpies of reactions. All of these constituents are illustrated in thermochemical equations and we can prove that the individual equations sum up to the main target chemical equation by cancelling out repeating compounds and elements and thereby leaving the lone standing chemical equation. Doing this process requires shifting the yield sign leading to a respective change in positive and negative symbol.