Why is sulphuric acid needed as a catalyst in an esterification reaction?
esterification is a reversible reaction and gives water as the 2nd product. By le Chatelier’s Principle, removing or decreasing the concentration of one of the products shifts the equilibrium to the right and favours the formation of the ester and of water. Sulphuric acid is hygroscopic (it absorbs water). By absorbing water, sulphuric acid decreases the amount of one of the products (water) and thus, as equilibrium shifts to the right, formation of the ester is promoted! That’s what we always want: find a way of obtaining as much of a desired product as possible!
