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Kinetics is about the rate at which things react (quickly, slowly) while thermodynamics is about stability in different states. One focuses on movement and change while the other on stability. It may also be noted they have different quantities. Free energy vs activation energy.
Another aspect of kinetics is that we're considering rates (derivatives), which become time and activity dependent. This helps to give a context in exactly what we're analyzing in terms of the reaction. In thermodynamics, we didn't particularly study any rates of activity.
Thermodynamics tells us if a forward or reverse reaction is favored. Kinetics tells us how fast the reaction is and the likelihood of the reaction occurring. Just because a reaction is thermodynamically favored does not mean it is kinetically favored. For example, the reaction of diamond to graphite is spontaneous, but diamond is kinetically stable with respect to graphite due to the large activation energy.
Like the other responses, thermodynamics gives no information based on time or the rate of the reaction. This information involves activation energy, which is a study included in kinetics. Kinetics focused on the rate of the reaction itself whereas thermodynamics can say if a reaction were to be spontaneous.
Raj_Bains_2C wrote:Thermodynamics only cares about the initial and final states, while kinetics focuses on the pathway of the reaction.
Thermodynamics only cares about the initial and final states unless you are considering heat and work, both of which are not state functions
Kinetics tells you the rate of the reaction; a reaction might be deemed spontaneous due to thermodynamics, but sometimes that reaction occurs very slowly. Kinetics tells you how fast or slow that reaction occurs.
Thermodynamics determines the spontaneity of the reaction, but will not tell if the reaction will occur slowly or quickly. We use kinetics to determine the rate of the actual reaction, dependent on the rate law constant; if the activation energy is high then the constant will be smaller and vice versa.
Even if someone is thermodynamically favored, the reaction may not occur becasue of the rate of reaction. For example, Graphite is more Thermodynamically favored than diamond, but the activation energy for that reaction is extremely high for some reason so Diamond will never spontaneously turn into Graphite
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