One of the properties of sodium metal that makes it an interesting element is it's explosive reaction when combined with water. Water has the molecular formula H2O, when combined with sodium, the sodium liberates a H+ ion and combines with the OH- ion to produce sodium hydroxide, a base. Sodium reacts with the OH- ion so well, it has to be stored in a liquid hydrocarbon, something that does not have oxygen or the hydroxyl ion present.
The chemical formula for ethanoic acid is CH3COOH. If sodium were introduced to ethanoic acid, we would probably see a similar reaction to the one described above with water. The sodium would take the OH- to form sodium hydroxide; I am not sure what the hydro carbon would be that would be produced as a result of the reaction. The presence of oxygen in the ethanoic acid tends to suggest a reaction would occur.