Lactic Acid Formula
The formula for lactic acid is C3H6O3. Its IUPAC name is 2-hydroxypropanoic acid. Its structure is made up of carboxyl (–COOH) and a hydroxyl (–OH) bounded by propane backbone.
Physical Properties of Lactic Acid
Appearance: Colorless or slightly yellow-colored liquid.
Odor: Mild, characteristic odor.
Boiling Point: About 122°C at 15 mmHg (252°F).
Melting Point: About 16.7°C (62°F).
Solubility: Highly soluble in water.
Density: About 1.209 g/cm³ at 20°C.
pH: Normally acid, about 2.4 for a 1 M solution.
Chemical properties of Lactic Acid
Acidity: It is a weak acid; hence, it partially dissociates in water, forming lactate ions-in other words, C₃H₅O₃⁻and hydrogen ions, H⁺.
Estimation: Lactic acid can undergo esterification with alcohol. Usually, this reaction is catalyzed by acid or base and also finds its applications in several industrial processes.
Reduction: Lactic acid is reduced by reducing agents to propan-1-ol.
Oxidation: On certain conditions, it gets oxidized into pyruvic acid.
Salts: Lactic acid forms lactic acid salts with bases. For instance, sodium hydroxide, forms sodium lactate, and potassium hydroxide, forms potassium lactate.
Decarboxylation: Lactic acid, under specific conditions, may lose carbon dioxide to form acetaldehyde. This is one of the less common reactions as compared to the rest of them.
Application of Lactic Acid
Preservative: It is used as a preservative and an acidulant in food.
Fermentation: This product is used during the fermentation of milk in the manufacturing of yogurt and cheese.
pH Regulator: The ingredient has been employed to reduce acidity over a wide range of processed foods and beverages.
Drug Delivery: The ingredient is employed to formulate various biodegradable delivery systems.
pH Adjuster: The ingredient provides sparing effects for maintaining pH during the administration of various medications.
Exfoliant: The AHA products serve to exfoliate the skin and prepare it for renewal.
pH Balancer: This chemical is used in cosmetic industries to balance pH in many cosmetic products.
Poly(lactic acid) (PLA): A biodegradable plastic that normally finds its application in the forms of disposable and packaging.
Solvent and Cleaner: It finds its application as a solvent and cleaning agent in industries.
Chemical Intermediate: The substance acts like an intermediary in the manufacturing of other chemical substances such as lactates and acrylic acid.
Soil Conditioners: Used in treating and improving soil conditions in certain agricultural activities.
Buffer Agent: This chemical is used in a variety of biochemical tests and applications as a reagent in the laboratory.
Conclusion
Lactic acid is a very versatile chemical that finds its applications across a broad gamut of industries. In the food industry, it plays both an important role as a preservative and an enhancer of flavor, to its functions in pharmaceuticals, especially in drug delivery, further in cosmetics by skin care. In addition, its use in bioplastics underlines its potential for sustainable materials. Lactic acid is important to both industrial applications and research due to its capabilities of acting as a solvent, cleaner, and buffering agent. Having various uses with several beneficial properties makes it quite useful in chemical applications commercially and scientifically.