What is the difference between carbonate and bicarbonate?

Carbonate and bicarbonate are both chemical compounds containing carbon and oxygen, but they differ in their chemical formulas and chemical properties.

Carbonate: Carbonate is an ion with the chemical formula CO3^2-. It consists of one carbon atom bonded to three oxygen atoms. Carbonates are typically formed by the reaction of carbon dioxide (CO2) with bases or metal oxides. Some examples of common carbonates include calcium carbonate (CaCO3), sodium carbonate (Na2CO3), and potassium carbonate (K2CO3). Carbonates are generally insoluble in water, except for alkali metal carbonates and ammonium carbonate.

Bicarbonate: Bicarbonate is an ion with the chemical formula HCO3-. It is derived from carbonic acid (H2CO3) by replacing one hydrogen atom with a metal or another positive ion. Bicarbonates are formed when carbon dioxide dissolves in water, leading to the formation of carbonic acid, which then dissociates into bicarbonate and hydrogen ions. Sodium bicarbonate (NaHCO3) and potassium bicarbonate (KHCO3) are examples of commonly encountered bicarbonates. Bicarbonates are soluble in water and are involved in many important biological processes, such as maintaining the pH balance in blood and acting as a buffer.

In summary, the main difference between carbonate and bicarbonate lies in their chemical formulas and solubilities. Carbonate (CO3^2-) has a higher charge and is typically insoluble in water, while bicarbonate (HCO3-) has a lower charge and is soluble in water.