kalciumvätekarbonat

Kalciumvätekarbonat, also known as calcium bicarbonate, is a chemical compound with the formula Ca(HCO3)2. It is the acid salt of calcium and carbonic acid. In its solid form, calcium bicarbonate is unstable and readily decomposes to calcium carbonate, water, and carbon dioxide, especially when heated or when exposed to air. Therefore, it is typically found dissolved in water.

This compound is primarily encountered in natural water sources. When rainwater, which is slightly acidic due to dissolved carbon dioxide, percolates through limestone or chalk deposits (which are largely composed of calcium carbonate), it reacts to form calcium bicarbonate. This process is known as the formation of temporary hardness in water. The presence of calcium bicarbonate in water contributes to its hardness and can lead to the formation of scale in pipes and appliances when the water is heated, as the bicarbonate decomposes back into insoluble calcium carbonate.

Calcium bicarbonate is not commonly isolated or sold as a pure substance due to its instability. However, its presence is significant in geological processes and water chemistry. In biological contexts, while calcium is an essential nutrient, calcium bicarbonate itself is not a primary dietary supplement; other more stable calcium compounds are used for this purpose. The term "kalciumvätekarbonat" is the Swedish name for this compound.