Answer to Question #37429 in Chemistry for calum

Question

What are the advantages and disadvantages of acetic acid as a de-scaler?

Answer 1

Acetic acid, more correctly called ethanoic acid, is a weak acid which will dissolve limescale, which is mostly CaCO3. Acetic acid CH3COOH is a weak acid with one ionizable proton which will react with carbonates to produce a solution calcium acetate and CO2 gas.

2CH3COOH(aq) + CaCO3(s) --> (CH3COO)2Ca(aq) + CO2(g) + H2O(l)

Since all acids react with carbonates to produce CO2, the best acids to use are those which are least toxic. Acetic acid is found in vinegar which is used to flavor the food we eat. Acetic acid, as vinegar, is a common choice for removing limescale because of its cheap cost and ready availability.