$$CaCO3_{(s)} + 2CH3COOH_{(aq)} → Ca(CH3COO)2_{(aq)} + H2O_{(l)} + CO2_{(g)}$$
In this reaction, calcium carbonate, a base, reacts with methanoic acid, also known as formic acid, an acid, to produce calcium methanoate (calcium formate), water and carbon dioxide gas.
