Does adding H2SO4 increase the yield of esterification? (1 Viewer)

[lolmb]

Hi,

Those familiar with the Jacaranda Chemistry textbook,it says "The concentrated sulfuric acid that is used as a catalyst also acts as a dehydrating agent. When water is removed from the reaction equilibrium, the equilibrium shifts to the right and increases the yield of ester."

But from my knowledge, changes in quantity of liquid or solid species doesn't affect concentration and hence position of equilibrium. therefore there shouldn't be any change in yield...

Could someone clear this up for me please?

Thanks

 

[Ekman]

Ok so adding in h2so4 in an esterification reaction is a special case. First of all, it is a catalyst so all it does is increase the rate of reaction, not increase yield. The reason why h2so4 may increase yield is a complex case. The one thing you must understand that changes in volume of liquid is all relative. If I decrease the amount of water in the esterification reaction, the concentration of water RELATIVE to the solution will also decrease. Thus the equilibrium will shift. So you must understand that changing volumes of liquids is all relative in equilibrium reactions. And so since water is a small by-product of esterification, its concentration relative to the main solution decreases as you add h2so4, thus increasing the yield. So far only esterification reactions are the only ones ive seen that require you to think about the concentration of a liquid relative to the main solution. Hope this answers your question