Magnesium bicarbonate or magnesium hydrogencarbonate,
Mg(
H CO3)
2, is the
bicarbonate
In inorganic chemistry, bicarbonate (IUPAC-recommended nomenclature: hydrogencarbonate) is an intermediate form in the deprotonation of carbonic acid. It is a polyatomic anion with the chemical formula .
Bicarbonate serves a crucial biochem ...
salt of
magnesium
Magnesium is a chemical element with the symbol Mg and atomic number 12. It is a shiny gray metal having a low density, low melting point and high chemical reactivity. Like the other alkaline earth metals (group 2 of the periodic ta ...
. It can be formed through the reaction of dilute solutions of
carbonic acid (such as
seltzer water
Carbonated water (also known as soda water, sparkling water, fizzy water, club soda, water with gas, in many places as mineral water, or especially in the United States as seltzer or seltzer water) is water containing dissolved carbon dioxide gas, ...
) and
magnesium hydroxide
Magnesium hydroxide is the inorganic compound with the chemical formula Mg(OH)2. It occurs in nature as the mineral brucite. It is a white solid with low solubility in water (). Magnesium hydroxide is a common component of antacids, such as milk ...
(milk of magnesia).
It can be prepared through the synthesis of
magnesium acetate and
sodium bicarbonate:
::
Magnesium bicarbonate exists only in aqueous solution. Magnesium does not form solid bicarbonate as does lithium. To produce it, a suspension of magnesium hydroxide is treated with pressurized
carbon dioxide
Carbon dioxide ( chemical formula ) is a chemical compound made up of molecules that each have one carbon atom covalently double bonded to two oxygen atoms. It is found in the gas state at room temperature. In the air, carbon dioxide is trans ...
, producing a solution of magnesium bicarbonate:
::Mg(OH)
2 + 2 CO
2 → Mg(HCO
3)
2
Drying the resulting solution causes the magnesium bicarbonate to
decompose
Decomposition or rot is the process by which dead organic substances are broken down into simpler organic or inorganic matter such as carbon dioxide, water, simple sugars and mineral salts. The process is a part of the nutrient cycle and is ...
, yielding
magnesium carbonate, carbon dioxide, and water:
::Mg
2+ + 2 HCO
3− → MgCO
3 + CO
2 + H
2O
References
{{Carbonates
Magnesium compounds
Bicarbonates