Please choose the correct ending to complete the given sentence: Education and Communications: [header] How to study states of equilibria in organic reactions [title] Understand what happens when equilibrium occurs. [step] Chemical reactions that reach a state of thermodynamic equilibrium are typical of uncatalyzed reactions in which their energy profile shows net enthalpy change of the reaction that is close to zero. This means that the reaction neither releases heat nor absorbs heat.

Ending1: This type of reaction is not driven by thermodynamic force so that it reaches a state of equilibrium. Normally other thermodynamic functions are affected by this state of equilibrium. Ending2: This can take you (and your listeners) two hours hours to complete. [title] Consider what kind of response you're planning to observe and read about before you begin your study. Ending3: The process is set to not again be dependent upon the new substance and as its dosage changes it is more responsive to change. It can work for a variety of reasons. Ending4: In fact, without change, the whole matter remains stationary. This results in a smooth, accelerated reaction.

Answer format: ending1/ending2/ending3/ending4