carbonic acid(redirected from H2CO3)
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carbonic acid,H2CO3, a weak dibasic acid (see acids and basesacids and bases,
two related classes of chemicals; the members of each class have a number of common properties when dissolved in a solvent, usually water. Properties
..... Click the link for more information. ) formed when carbon dioxidecarbon dioxide,
chemical compound, CO2, a colorless, odorless, tasteless gas that is about one and one-half times as dense as air under ordinary conditions of temperature and pressure. It does not burn, and under normal conditions it is stable, inert and nontoxic.
..... Click the link for more information. dissolves in water; it exists only in solution. Carbonic acid forms carbonate and bicarbonate (or acid carbonate) salts (see carbonatecarbonate
, chemical compound containing the carbonate radical or ion, CO3−2. Most familiar carbonates are salts that are formed by reacting an inorganic base (e.g., a metal hydroxide) with carbonic acid.
..... Click the link for more information. ) by reaction with bases. It contributes to the sharp taste of carbonated beverages.
H2CO3, a weak dibasic acid that under normal conditions exists only in dilute aqueous solutions. Carbonic acid is formed when carbon dioxide dissolves in water: . Under normal conditions, the total amount of carbonic acid in a solution saturated with CO2 does not exceed 1 percent of the CO2 content. The dissociation constants are K1 = 4.0 × 10–7 and K2 = 5.2 × 10–11 at 18°C. Carbonic acid decomposes completely when its solutions are heated, liberating CO2. Depending on the basicity, the acid forms two series of salts. The neutral salts, known as carbonates, have the anion, and the acid salts, known as bicarbonates, have the anion.