Acetic acid - New World Encyclopedia
网页Acetic acid is a weak, effectively monoprotic acid in aqueous solution, with a pK a value of 4.8. Its conjugate base is acetate (CH 3 COO −). A 1.0 M solution (about the concentration of domestic vinegar) has a pH of 2.4, indicating that merely 0.4 percent of the acetic acid molecules are dissociated. Cyclic dimer.
Acid - New World Encyclopedia
网页Common weak acids are nitrous acid (HNO 2), hydrofluoric acid (HF), and acetic acid (CH 3 CO 2 H). For example, the K a value for acetic acid is 1.8 x 10-5. Note on terms used: The terms "hydrogen ion" and "proton" are used interchangeably; both refer to H +. In aqueous solution, the water is protonated to form hydronium ion, H 3 O + (aq).
Vinegar - New World Encyclopedia
网页Vinegar. Vinegar is a sour liquid produced from the fermentation of diluted alcohol products, which yields the organic compound acetic acid, its key ingredient. Used in many cultures as a condiment and preservative, vinegar can be made from a variety of liquids, including malted barley, rice, and cider; however, as its name suggests, it was ...
Azeotrope - New World Encyclopedia
网页Distilling the solution to dry acetic acid is therefore economically impractical. But ethyl acetate forms an azeotrope with water that boils at 70.4°C. By adding ethyl acetate as an entrainer, it is possible to distill away the azeotrope and leave nearly pure acetic acid as the residue. Why azeotropes exist
Ethyl acetate - New World Encyclopedia
网页Ethyl acetate is an organic compound that is an ester derived from the combination of ethanol and acetic acid. Its chemical formula may be written as CH 3 CH 2 OC(O)CH 3 or CH 3 CO 2 C 2 H 5, and chemists often abbreviate its name as EtOAc. It is a colorless liquid with a characteristic smell that is slightly sweet and fruity.
Carboxylic acid - New World Encyclopedia
网页Acid-base reactions: A carboxylic acid reacts with a base to form a carboxylate salt in which the hydrogen of the carboxyl group is replaced with a metal cation. For instance, acetic acid reacts with sodium hydroxide (a base) to produce sodium acetate, a water-soluble salt, and water. The reaction may be written as: CH 3 COOH + NaOH → CH 3 ...
Salicylic acid - New World Encyclopedia
网页Salicylic acid is a crystalline, solid (up to 159 o C) organic acid that is used to make aspirin and various pharmaceutical products. It also functions as a plant hormone. The name salicylic acid derives from the Latin word for the willow tree (Salix), from whose bark it can be obtained (Mackowiak 2000). Originally recognized in ancient times ...
Pyruvic acid - New World Encyclopedia
网页Pyruvic acid is a colorless liquid with a smell similar to that of acetic acid. It is miscible with water, and soluble in ethanol and diethyl ether . In the laboratory, pyruvic acid may be prepared by heating a mixture of tartaric acid and potassium hydrogen sulfate, or by the hydrolysis of acetyl cyanide (CH 3 COCN), formed by reaction of ...
Acetaldehyde - New World Encyclopedia
网页Acetaldehyde, sometimes known as ethanal, is an organic chemical compound with the formula C H 3 CH O (or MeCHO). It is a flammable liquid with a fruity smell. It occurs naturally in ripe fruit, coffee, and fresh bread and is produced by plants as part of their normal metabolism.
Acetaminophen - New World Encyclopedia
网页When the cinchona tree became scarce in the 1880s, people began to look for alternatives. Two antipyretic agents were developed in the 1880s: acetanilide in 1886 and phenacetin in 1887. By this time, acetaminophen had already been synthesized by Harmon Northrop Morse via the reduction of p-nitrophenol with tin in glacial acetic acid. While this ...