Sodium bicarbonate

Sodium bicarbonate has the IUPAC name Sodium hydrogen carbonate with the formula NaHCO₃. It is a white solid that is crystalline but often appears as a fine powder. It will melt at 50 °C which is soluble in water. It is stable at normal pressure and temperature. The substance should be stored at cool, dry, well-ventilated place. In addition, it should be protected from strong oxides and acids. Sodium bicarbonate is amphoteric which can react with acids and bases. With the CAS register number of 144-55-8, the substance also has the EINECS registry number 205-633-8.

Properties: Sodium bicarbonate is a component of the mineral natron and is found dissolved in many mineral springs. The substance is an amphoteric compound. Aqueous solutions are mildly alkaline due to the formation of carbonic acid and hydroxide ion. Sodium bicarbonate reacts with bases such as sodium hydroxide to form carbonates. Sodium bicarbonate and an acid can react to give a salt and carbonic acid which readily decomposes to give carbon dioxide and water. Sodium bicarbonate will gradually decompose into sodium carbonate and carbon dioxide above 70 °C. The conversion is more fast at 200 °C.

HCO₃^- + H₂O → H₂CO₃ + OH-
NaHCO₃ + NaOH → Na₂CO₃ + H₂O
NaHCO₃ + HCl → NaCl + H₂O + CO₂(g)
2 NaHCO₃ → Na₂CO₃ + H₂O + CO₂

Preparation: Sodium bicarbonate is mainly prepared by the Solvay process, which is the reaction of calcium carbonate, sodium chloride, ammonia, and carbon dioxide in water. It may be obtained by the reaction of carbon dioxide with an aqueous solution of sodium hydroxide. The initial reaction produces sodium carbonate. Further addition of carbon dioxide produces sodium bicarbonate.

CO₂ + 2 NaOH → Na₂CO₃ + H₂O
Na₂CO₃ + CO₂ + H₂O → 2 NaHCO₃

Uses: The Sodium bicarbonate was used as a cleansing agent like soap. Sodium bicarbonate was sometimes used in cooking vegetables, to make them softer. As a leavening agent, Sodium bicarbonate is primarily used in cooking. Sodium bicarbonate can be used as a wash to remove any acidic impurities from a "crude" liquid, producing a purer sample. Sodium bicarbonate can be added as a simple solution for raising the pH balance of water. Sodium bicarbonate is used in an aqueous solution as an antacid. Sodium bicarbonate is sold as a cattle feed supplement, in particular as a buffering agent for the rumen. It may also be used in an oral form to treat chronic forms of metabolic acidosis such as chronic renal failure and renal tubular acidosis. Sodium bicarbonate may also be used in urinary alkalinization for the treatment of aspirin overdose and uric acid renal stones. It is used as the medicinal ingredient in gripe water for infants. It is used as well for treatment of hyperkalemia. Sodium bicarbonate can be used as an exfoliant. Small amounts of Sodium bicarbonate have been shown to be useful as a supplement for endurance athletes. Sodium bicarbonate can be used to extinguish small grease or electrical fires by being thrown over the fire. However, as it may cause the grease to splatter, it should not be applied to fires in deep fryers.

Descriptors computed from structure of Sodium bicarbonate:
(1)Canonical SMILES: C(=O)(O)[O-].[Na+]
(2)InChI: InChI=1S/CH2O3.Na/c2-1(3)4;/h(H2,2,3,4);/q;+1/p-1
(3)InChIKey: UIIMBOGNXHQVGW-UHFFFAOYSA-M

Toxicity of Sodium bicarbonate: