Reaction of Carboxylic Acids with Carbonates

Carboxylic acids react with carbonates and hydrogencarbonates to form a salt, carbon dioxide and water.

The hydrogen in the hydroxyl part of the carboxylic group is lost and replaced with the metal of the salt. For example in the reaction of ethanoic acid with sodium carbonate:

The equation above is unbalanced but shows the hydrogen (blue) in the hydroxyl part of the carboxylic group is lost and replaced by the sodium (red). The resulting bond between the sodium and the ethanoate group is ionic. It must not be represented by a line between the two atoms as this would represent a covalent bond.

 

 

Methanoic Acid Reaction with a Carbonate

Methanoic acid + sodium carbonate → sodium formate + water + carbon dioxide

2HCOOH(aq) + Na₂CO₃(s) → 2HCOONa(aq) +H₂O(l) + CO₂(g)

 

Ethanoic Acid Reaction with a Carbonate

Ethanoic acid + sodium carbonate → sodium ethanoate + water + carbon dioxide

2CH₃COOH(aq) + Na₂CO₃(s) → 2CH₃COONa(aq) +H₂O(l) + CO₂(g)

 

Propanoic Acid Reaction with a Carbonate

Propanoic acid + sodium carbonate → sodium propanoate + water + carbon dioxide

2C₂H₅COOH(aq) + Na₂CO₃(s) → 2C₂H₅COONa(aq) +H₂O(l) + CO₂(g)

 

Butanoic Acid Reaction with a Carbonate

Butanoic acid + sodium carbonate → sodium butanoate + water + carbon dioxide

2C₃H₇COOH(aq) + Na₂CO₃(s) → 2C₃H₇COONa(aq) +H₂O(l) + CO₂(g)

 

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