When a chemical reaction is carried out in an industrial setting, it is very common to have one of the reactants present in an excess amount above the stoichiometric quantity that would be needed for the reaction. Why?
When a chemical reaction is carried out in an industrial setting, it is common to have one of the reactants present in an excess amount above the stoichiometric quantity. This practice has several reasons:
1. Efficiency: Having an excess of one reactant ensures that the reaction proceeds to completion, maximizing the yield of the desired product. By providing more than the required amount, any limitations or inefficiencies of the reaction can be compensated for, increasing the overall reaction efficiency.
2. Cost-effectiveness: Some reactants can be expensive or difficult to obtain. By using an excess of the more readily available reactant, costs can be reduced. This excess reactant can also be recycled and reused in subsequent reactions, improving cost-effectiveness.
3. Reaction kinetics: In some cases, having an excess reactant can accelerate the reaction rate. This is especially relevant for reactions that are slow or have high activation energies. By providing more of one reactant, the reaction rate can be increased, reducing the reaction time required.
4. Safety considerations: In certain reactions, having an excess of one reactant can serve as a safety precaution. If there is the possibility of an unexpected reaction or if hazardous by-products are formed, diluting them with an excess reactant can mitigate the risk.
It is important to note that the choice of which reactant to use in excess is carefully considered, taking into account the factors mentioned above and other factors specific to the reaction and industrial process.