bicarbonate

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bicarbonate

chemical compound

Also known as: hydrogen carbonate

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June 22, 2026

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Bicarbonate is a chemical compound that can exist in various forms, most commonly as sodium bicarbonate (NaHCO₃) or ammonium bicarbonate (NH₄HCO₃). Sodium bicarbonate, also known as baking soda, is a white, crystalline solid used in baking powders, effervescent salts, and fire extinguishers. Its mild alkalinity also makes it useful for treating acidity.123

Carbonic acid (H₂CO₃) is formed when carbon dioxide dissolves in water. This acid plays a role in cave formation and is crucial for transporting carbon dioxide in the blood. Bicarbonate ions (HCO₃^-) are formed from carbonic acid and are essential for buffering blood pH. Calcium bicarbonate (Ca(HCO₃)₂) is formed when carbon dioxide-rich water dissolves calcium carbonate.456

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oxyacid
Carbonate and hydrogen carbonate salts
These salts can be prepared by the reaction of carbon dioxide with metal oxides and metal hydroxides, respectively.CO₂ + O₂ → CO₃²⁻
CO₂ + OH⁻ → HCO₃⁻ For example, when an aqueous solution of sodium hydroxide (NaOH) is saturated with carbon…
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These salts can be prepared by the reaction of carbon dioxide with metal oxides and metal hydroxides, respectively.CO₂ + O₂ → CO₃²⁻
CO₂ + OH⁻ → HCO₃⁻ For example, when an aqueous solution of sodium hydroxide (NaOH) is saturated with carbon…
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blood
Plasma
Bicarbonate participates in the transport of carbon dioxide and in the regulation of pH. Phosphate also has a buffering effect on the pH of the blood and is vital for chemical reactions of cells and for the metabolism of calcium. Iodide is transported through plasma…
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Bicarbonate participates in the transport of carbon dioxide and in the regulation of pH. Phosphate also has a buffering effect on the pH of the blood and is vital for chemical reactions of cells and for the metabolism of calcium. Iodide is transported through plasma…
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human digestive system
Vasoactive intestinal peptide
…is a mild stimulant of bicarbonate secretion from the pancreas, and is a powerful stimulant of the secretion of water and electrolytes by the small and large intestines. It relaxes the sphincters and slows intestinal transit time. There is another group of peptide messengers that is found in quantity within…
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…is a mild stimulant of bicarbonate secretion from the pancreas, and is a powerful stimulant of the secretion of water and electrolytes by the small and large intestines. It relaxes the sphincters and slows intestinal transit time. There is another group of peptide messengers that is found in quantity within…
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human disease
Fluid and electrolyte balance
…extracellular fluid is chloride, while bicarbonate is the second most important. In contrast, the major cation of the intracellular fluid is potassium, and the major anions are proteins and organic phosphates. The marked differences in sodium and potassium concentrations between the intracellular and extracellular fluid of cells are not fortuitous…
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…extracellular fluid is chloride, while bicarbonate is the second most important. In contrast, the major cation of the intracellular fluid is potassium, and the major anions are proteins and organic phosphates. The marked differences in sodium and potassium concentrations between the intracellular and extracellular fluid of cells are not fortuitous…
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renal system
Regulation of acid-base balance
, filtered bicarbonate). Current evidence indicates that both filtration and secretion are essential to hydrogen ion excretion and that both proximal and distal convoluted tubules are involved.
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, filtered bicarbonate). Current evidence indicates that both filtration and secretion are essential to hydrogen ion excretion and that both proximal and distal convoluted tubules are involved.
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