An organic acid is an organic compound having properties of acids. It is an acid occurring naturally in foods that contain carbon, for example acetic acid, citric acid, fumaric acid, lactic acid, malic acid, etc. Those organic compounds having functional group COOH behave like acids are also thereby termed as organic acids.
What is Organic Compound? An organic compound is any member of a large class of chemical compounds the molecules of which contain carbon.
What is Acid? An acid (often represented by the generic formula HA) is traditionally considered any chemical compound that, when dissolved in water, gives a solution with a pH less than 7.0.
Types of Organic Acids Organic acids are of two types: » COOH group (the carboxyl group) » Phenol group Each type appears in salicylic acid (OHC6H4COOH). Water solutions of each type are weakly acidic. Phenol is also known as Carbolic Acid, Benzenol, Phenylic Acid, Hydroxybenzene and Phenic acid.
Phenol has antiseptic properties, which was used by Sir Joseph Lister (1827-1912) in his pioneering technique of antiseptic surgery
It is used as an active ingredient in some oral anesthetics such as Chloraseptic spray
Phenol was the main ingredient of the Carbolic Smoke Ball, a device sold in London, which protected the user against influenza and other ailments
It is used in the manufacture of drugs, weedkiller and synthetic resins
Phenol is used in cosmetic surgery as an exfoliant to remove layers of dead skin
It is used in phenolization, a surgical procedure used to treat an ingrown nail
Characteristics of Organic Acid
Organic acids having 4 to 9 carbon atoms are colourless oily liquids at ordinary room temperatures
Organic acids are weak acids and do not dissociate completely
Lower molecular weight organic acids can be mixed in water
Higher molecular weight organic acids are insoluble in molecular form
Most organic acids are very soluble in organic solvents
It has variety in the chemical structure
Several types of toxic effects may occur in organic acids
Organic acids with 1 to 3 carbon atoms are colorless liquids at ordinary room temperatures. Those with higher molecular weights have a primary irritant effect, the degree determined in part by acid dissociation and water solubility
Organic acids with 1 to 3 carbon atoms have very pungent smell. The next acids with 4 to 9 carbon atoms smell like goatâ€™s butter. Still higher molecular weighted organic acids are odorless
The first four carbonic acids are soluble in water. As the molecular weight increases, the solubility in water decreases
Organic acids like methanoic and ethanoic acids turn blue litmus to red quite easily
Organic acid reacts with sodium bicarbonate to release water and carbon dioxide.
Hazards of Organic Acid All organic acids except monocarboxylic acids are user-friendly. The low-molecular-weight monocarboxylic acids are primary irritants and cause severe damage to tissues. Strict precautions are necessary in handling this acid. Suitable protective equipment should be available for protection of the skin or eye while one works with this acid. The most important acids of this group are acetic acid and formic acid.
Application of Organic Acid
Simple organic acids like formic or acetic acid are used for oil and gas cell stimulation treatments
The conjugate bases of organic acids such as citrate and acetate are often used in biologically-compatible buffer solutions
Organic acids are valuable platform chemicals for future biorefining applications
The use of organic acids improves the yield of certain crops
It is used in nearly every type of chemical manufacture
Organic acids have wide application in the plastics, tanning, textile, paper, metal, pharmaceutical, food, beverage and cosmetics industries
They are used in perfumes, herbicides, dyes, lubricants and cleaners
Organic acids are used in some food items. For example vinegar is dilute acetic acid, which is used in many preparations for pickles, salads, sauces, etc.
Acetic acid, an organic acid is used for coagulation of latex, which is needed when rubber is made from latex in a rubber manufacturing industry
Acetic acid is also used for making cellulose acetate, which is an important starting material for making artificial fibers.