carbonic acid

carbonic acid (uncountable)

1. (organic chemistry) A weak unstable acid, H₂CO₃, known only in solution, and as carbonate salts; it is present in carbonated drinks, and sparkling wine, but decomposes to form carbon dioxide and water.

   Synonym: H₂CO₃

   • 1837, L[etitia] E[lizabeth] L[andon], Ethel Churchill: Or, The Two Brides. […], volume II, London: Henry Colburn, […], →OCLC, pages 110–111:

     Had she lived now, she would have talked of the last delightful lecture on gas, or the charming new treatise on carbonic acid; she would have studied German, and delighted in the society of "talented people."

   • 1898, H.G. Wells, The War of the Worlds, London: William Heinemann, page 144:

     [I]t sank down through the air and poured over the ground in a manner rather liquid than gaseous, abandoning the hills, and streaming into the valleys and ditches and water-courses even as I have heard the carbonic acid gas that pours from volcanic clefts is wont to do.

2. (obsolete) Carbon dioxide.

• carbonic acid gas
• carbonic acid snow