Equation for sodium carbonate extracting ethanoic acid from an ester?

Question

I need to explain with the aid of an equation the reason for adding sodium carbonate solution to an ester (pentyl ethanoate) prepared under reflux. The sodium carbonate is added to extract the ethanoic acid from the ester mixture.

How could I write this equation?

Thanks.

Answer 1

I think what you're describing is how to work up a Fischer Esterification reaction. Pentylethanoate, which is CH3(CH2)4-OCOCH3, is made by refluxing pentanol and acetic acid with an acid catalyst such as sulfuric acid (H2SO4). You would want to extract the reaction mixture with sodium carbonate to remove any unreacted acetic acid (CH3COOH). The reaction to do this would be as follows...

CH3COOH + Na2CO3 --> CH3COO-Na+ (sodium acetate) + NaHCO3 (sodium bicarbonate)...

Hope this helps!!!