Say we have a closed system in equilibrium. We remove some products, and thus cause the reaction to shift to the right and products to be produced. However, according to LCP, the concentration of products will never reach the concentration of the original equilibrium. Does this mean that the yield of the reaction has decreased relative to the original equilibrium? Shouldn't we have "more products" if we include the products we took out and the products the system produced?
With LCP, removing products shifts the system to the right, correct. This will shift the remaining reactants to balance the equilibrium again, but the concentration won't be the same since no new reactants were added.
The yield is actually increased because more product was produced, including your removed products. This is actually used in industry such as dehydration of ethanol.
}\rightarrow\ce{C2H4(g)}+\ce{H2O(g)})
The reaction uses a concentrated sulfuric acid catalyst as a dehydrating agent to remove water as it forms. This shifts the reaction spontaneously to the right, thus massively boosting the yield of ethene that would have been much less. This is also used in the Haber Process (liquefying ammonia), and in esterification (dehydrating water).
Basically, removing products is used to boost yield since you also have the removed products. In practice, they usually add more reactants into the vessel as they remove products because they want to continue the system.
Hope this helps
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