cas number glacial acetic acid

Understanding Glacial Acetic Acid Properties, Applications, and Safety

Glacial acetic acid, chemically known as ethanoic acid, is an organic compound with the molecular formula CH3COOH. It is a colorless liquid that possesses a strong, pungent odor and is known for its ability to act as a weak acid. The term glacial refers to its ability to solidify at relatively low temperatures (specifically at about 16.6 degrees Celsius or 62 degrees Fahrenheit), forming a crystalline solid that resembles ice. This property of solidification at low temperatures provides both its name and its importance in various industrial and laboratory applications.

Chemical Properties

Glacial acetic acid is characterized by its high acidity compared to other carboxylic acids, allowing it to donate protons (H⁺ ions) in solution effectively. Its pKa value is around 4.76, making it a weak acid that can still engage in significant reactions with strong bases to form salts and water. Being a polar protic solvent, it has excellent solvation properties, enabling it to dissolve many ionic and polar compounds.

Among its notable physical properties, glacial acetic acid has a boiling point of 118.1 degrees Celsius and a density of 1.05 g/cm³. The substantial hydrogen bonding in glacial acetic acid results in a relatively high boiling point for a substance of its molecular weight. Because of its high miscibility with water, glacial acetic acid is frequently used as a solvent in various chemical reactions.

Glacial acetic acid is a fundamental chemical in the production of a wide array of products. Its most significant application is in the production of acetic anhydride and acetate esters, which serve as valuable intermediates in the manufacture of products like synthetic fibers, plastics, and food additives. For instance, acetate esters are commonly used as solvents in paint and coatings, whereas acetic anhydride is essential for producing pharmaceuticals, such as aspirin.

Furthermore, glacial acetic acid is employed in the food industry as a preservative and flavoring agent, especially in pickling processes. It is recognized by the FDA as a safe additive when used in moderation. Additionally, the textile industry leverages glacial acetic acid to assist in dyeing and finishing fabrics.

Laboratory Uses

In laboratory settings, glacial acetic acid is a vital reagent. It is often used in titrations and organic synthesis pathways, particularly in the formation of esters and as a solvent for various chemical reactions. Due to its properties, glacial acetic acid is used in polymer science and analytical chemistry for different analytical procedures.

Safety and Handling

While glacial acetic acid is widely used in various applications, it is essential to handle it with care due to its corrosive nature. Direct contact with skin or eyes can cause severe burns, and inhalation of vapors may result in respiratory irritation. Therefore, proper safety precautions, including the use of gloves, goggles, and fume hoods, are crucial when working with this compound. In case of exposure, immediate medical attention should be sought.

Storage of glacial acetic acid requires it to be kept in tightly sealed containers, away from heat sources and incompatible materials such as strong oxidizers and alkalis. In addition, it should be stored in a well-ventilated area to prevent the buildup of vapors.

Conclusion

In summary, glacial acetic acid is a versatile and widely used chemical with significant industrial and laboratory applications. Its unique properties make it indispensable in various fields, including pharmaceuticals, food production, and textiles. However, it is crucial to observe safety protocols to mitigate the risks associated with this potent acid. Understanding its characteristics, applications, and safety measures is vital for anyone working with or studying this important chemical compound.