𝑜 𝑐𝑎𝑛 𝑏𝑒 𝑑𝑒𝑡𝑒𝑟𝑚𝑖𝑛𝑒𝑑 𝑏𝑦 𝑎𝑛 𝑖𝑛𝑑𝑖𝑟𝑒𝑐𝑡 𝑎𝑝𝑝𝑟𝑜𝑎𝑐ℎ which is based on Hess's law, it can be stated as follows. When reactants are converted to products, the change in enthalpy is the same whether the reaction takes place in in one step or in a series of steps