Final answer:
Vinegar, containing acetic acid, reacts chemically with calcium carbonate lime deposits in coffee makers to form calcium acetate, water, and carbon dioxide, effectively cleaning the machine.
Step-by-step explanation:
When cleaning a coffee maker with vinegar, the reaction involved is a chemical one between acetic acid (found in vinegar) and the lime deposits, which are primarily composed of calcium carbonate. In this reaction, acetic acid (CH3COOH) reacts with the calcium carbonate (CaCO3) to form calcium acetate, water, and carbon dioxide gas. The effervescence observed is due to the release of carbon dioxide. This cleansing process is effective because vinegar, as a diluted solution of acetic acid, helps dissolve the lime deposits that hinder the performance of the coffee maker. After using vinegar, it is essential to run water through the brewing cycle to remove any residual acetic acid.