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| Equilibrium Reactions is Really Unexplainable |
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Chemical reactions is the process by which two or chemicals are mixed together, resulting in the production of a third product. Equilibrium reactions tend to reform back to their original states after two or more reactants are mixed together. With any chemical reactions the compounds go through stages of change. The end result is a new compound or product.
When the combination of equilibrium reactions and chemical reactions are combined the two reactants mixed together form another product. Equilibrium reactions is a pretty basic topic. First, when you have a system made up of a lot of molecules, those molecules sometimes combine. That's the idea of a chemical reaction. Second, a chemical reaction sometimes starts at one point and moves to another. The reaction finished and you have a pile of new chemicals. Those current chemicals want to go through a reverse chemical reaction and become the original molecules. It is not really known why this equilibrium reaction takes place. These products like to break apart and return the form of the original reactant. There is a point where those two reactions are combined and you can't tell that any reactions are occurring. That point is when the overall reaction is happy. There is no pressure to do more of one thing or another.
The concept of chemical equilibrium was introduced and developed by Berthollet (1803) He found that some chemical reactions are reversible. For any reaction to be an equilibrium reaction, the rates of the forward and backward (reverse) reactions have to be equal. The equilibrium position of a reaction is said to lie far to the right if, at equilibrium, nearly all the reactants are used up and far to the left if hardly any product is formed from the reactants. By convention the products form the numerator. But, the law of mass action is valid only for concerted one-step reactions that proceed through a single transition state and is not valid in general because rate equations do not, in general, follow the stoichiometry of the reaction as Guldberg and Waage had proposed. Equality of forward and backward reaction rates, however, is a necessary condition for chemical equilibrium, though it is not sufficient to explain why equilibrium occurs.
Despite the failure of this derivation, the equilibrium reactions is indeed a constant, independent of the activities of the various species involved. Though it does depend on temperature as observed by the van 't Hoff equation. Adding a catalyst will affect both the forward reaction and the reverse reaction in the same way and will not have an effect on the equilibrium constant. The catalyst will speed up both reactions thereby increasing the speed where by equilibrium is reached. Although the macroscopic equilibrium concentrations are constant in time, the reactions do occur at the molecular level. For example, in the case of ethanoic acid dissolved in water and creating ethanoate and hydronium ions, a proton may hop or skip from one molecule of ethanoic acid to a water molecule and then on to an ethanoate ion to form another molecule of ethanoic acid and leaving the number of ethanoic acid molecules unchanged.
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