Chemical Reactions

Kinetics and Thermodynamics

What does it mean when we say a chemical reaction takes one minute?

When we say a reaction takes one minute, what we’re really saying is that a certain fraction (specifically that fraction is 1-1/e, or about 63%) of the reactant molecules have gone on to form products after one minute has passed (e refers to the irrational number e = 2.7182818…). If we say a reaction takes one year, or any other amount of time, we’re also referring to that same fraction of reactants becoming products. It’s not that 100% of the reactants have become products, but rather just a certain fraction.


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