Excess Reactant
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Excess Reactant
When we have a limiting reactant in a chemical reaction that is completely used up, what happens to the reactant that is in excess? Does it exist alongside the products of the reaction? For example, if CaC2 (limiting reactant) reacts with H2O (excess reactant) to form Ca(OH)2 and C2H2, does the excess H2O exist with the Ca(OH)2 and C2H2 once CaC2 has been used up?
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Re: Excess Reactant
In theory yes, but remember that when the limiting reagent is completely "used up," this means that the reaction is in equilibrium. If the reaction is reversible, this means that the molecules will go back and forth between changing into reactants in products in a way that there are no net changes in the equilibrium concentrations. If the reaction is strictly a one-way reaction, then whatever is left of the excess reagent would kinda just sit there because it has nothing else to react with. This of course, refers to perfect experimental conditions where the only molecules present are the ones in the chemical formula.
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Re: Excess Reactant
It is not being used in the reaction to make products so its not included in the reaction but like physically its still there like you said.
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Re: Excess Reactant
As explained above, it doesn't do much and exists in excess because the limiting reactant is all used up
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Re: Excess Reactant
The limiting reactant is involved in reactions. These reactions are in equilibrium when the limiting reactant is used up. So the excess reactant is technically still there, but it is not used in the reaction.
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