Decarboxylation of carboxylic acids

The SODIUM salt of a carboxylic acid, heated together with soda lime (a mixture of sodium hydroxide and calcium oxide, CaO), undergoes DECARBOXYLATION -- it loses its carboxyl carbon entirely, as sodium carbonate, and gives back a hydrocarbon with exactly ONE fewer carbon atom than the original acid had: R-COONa + NaOH, with CaO and heat, gives R-H + Na2CO3. Worked example: sodium acetate (CH3-COONa), treated with NaOH/CaO and heat, gives methane (CH4) + sodium carbonate (Na2CO3) -- the simplest possible case, where the …