1. Acetic Acid (CH3COOH)
Structure:
Acetic acid is a simple carboxylic acid consisting of a methyl group (CH3) attached to a carboxyl group (COOH). It's the second smallest carboxylic acid (after formic acid) and is characterized by its pungent odor and sour taste.
Uses:
1. Vinegar: Diluted acetic acid (about 5-8% by volume) is known as vinegar, a staple in kitchens worldwide used for pickling, seasoning, and marinades.
2. Chemical Synthesis: It's a key raw material in the manufacture of vinyl acetate monomer (VAM), which is further used to produce polyvinyl acetate (PVA) and polyvinyl alcohol (PVOH).
3. Solvent: Acetic acid is used as a solvent in the production of terephthalic acid, used for making polyester fibers and PET plastic bottles.
4. Food Industry: As a food additive, it regulates acidity and has preservative qualities.
2. Lactic Acid (C3H6O3)
Structure:
Lactic acid or 2-hydroxypropanoic acid contains a hydroxyl group (-OH) adjacent to the carboxyl group, making it an alpha-hydroxy acid.
It's produced naturally in muscles during intense activity.
Uses:
1. Food Industry: As an acidulant in foods like yogurt and sourdough bread. It enhances flavor and extends shelf life.
2. Biodegradable Plastics: Polylactic acid (PLA) is derived from lactic acid and used to produce eco-friendly plastics.
3. Pharmaceuticals: Lactic acid is used in various medical products, including IV solutions and as a starting material for biodegradable sutures.
4. Cosmetics: In skin care products, it serves as a moisturizer, pH regulator, and exfoliant.
3. Tartaric Acid (C4H6O6)
Structure:
Tartaric acid is a dicarboxylic acid with two chiral centers, making it optically active.
It has two hydroxyl groups (-OH) and two carboxyl groups (COOH).
Uses:
1. Food Industry: As an acidulant in wine (to control acidity), baking powder (as a leavening agent), and in candies to impart a sour taste.
2. Pharmaceuticals: Used as a chiral resolution agent for asymmetric synthesis and as an excipient.
3. Metal Polishing and Tanning: Tartaric acid is used in metal polishing and tanning industries for its ability to chelate metals.
4. Citric Acid (C6H8O7)
Structure:
Citric acid is a tricarboxylic acid with three carboxyl groups.
It's an intermediate in the citric acid cycle (Krebs cycle), crucial for energy production in metabolism.
Uses:
1. Food and Beverages: As a flavor enhancer, preservative, and acidulant in soft drinks, candies, and jams.
2. Cleaning Agents: In eco-friendly cleaning products for its ability to dissolve hard water stains and build-ups.
3. Cosmetics: In beauty and skincare products, citric acid is used to adjust acidity and promote skin peeling and re-growth.
5. Succinic Acid (C4H6O4)
Structure:
Succinic acid is a dicarboxylic acid with a linear chain of two carbon atoms between two carboxyl groups. It's a component of the citric acid cycle.
Uses:
1. Chemical Industry: Precursor for the synthesis of polymers, resins, and solvents.
2. Food Additive: As an acidity regulator and flavor enhancer.
3. Pharmaceuticals: In dietary supplements for its supposed health benefits, including reducing pain and inflammation.
6. Oxalic Acid (C2H2O4)
Structure:
Oxalic acid is the simplest dicarboxylic acid, with two carboxyl groups directly bonded to each other.
It's found in many plants, notably rhubarb leaves.
Uses:
1. Cleaning Agent: Effective at removing rust and stains, particularly for minerals and metals.
2. Bleaching Agent: Used in the textile and wood industries to bleach or lighten color.
3. Chemical Synthesis: In organic synthesis as a reducing agent and for lanthanide extraction.
7. Salicylic Acid (C7H6O3)
Structure:
Salicylic acid is a type of phenolic acid and a beta hydroxy acid (BHA) with the formula C7H6O3.
It consists of a benzene ring bonded to a hydroxyl group (-OH) and a carboxylic acid group (-COOH) at adjacent positions, making it an ortho-hydroxybenzoic acid.
Uses:
1. Medicine: Widely used as an ingredient in topical acne treatments due to its ability to exfoliate the skin and clear pores. It's also used in wart removers and anti-dandruff shampoos.
2. Cosmetics: Incorporated in skin care products for its exfoliant properties to improve skin texture and appearance.
3. Pharmaceuticals: Salicylic acid is a precursor in the synthesis of aspirin (acetylsalicylic acid).
8. Benzoic Acid (C7H6O2)
Structure:
Benzoic acid is the simplest aromatic carboxylic acid, consisting of a benzene ring directly attached to a carboxylic acid group.
Uses:
1. Food Preservation: Utilized as a preservative in food and beverages due to its antimicrobial properties, often in the form of its salts (sodium benzoate).
2. Pharmaceuticals: Employed in the manufacture of various medicines, including as a precursor for the synthesis of salicylic acid.
3. Plasticizers: In the production of plasticizer precursors and benzoyl compounds used in the chemical industry.
9. Benzyl Benzoate (C14H12O2)
Structure:
Benzyl benzoate is an ester formed from the condensation of benzoic acid and benzyl alcohol.
It features a benzyl group attached to the benzoate ester functional group.
Uses:
1. Medical Treatments: Used as a treatment for scabies and lice, functioning as an acaricide that kills mites and lice.
2. Fragrance and Flavoring: Employed in the fragrance industry due to its sweet balsamic odor. It's also used as a flavoring agent.
3. Plasticizer: In the manufacture of cellulose and other polymers, acting as a solvent or plasticizer to improve material properties.
10.Dimethyl Phthalate (C10H10O4)
Structure:
Dimethyl phthalate is a phthalate ester with two methyl groups esterified to the phthalic acid.
It's characterized by two carboxylate groups attached to a benzene ring, each esterified with a methyl group.
Uses:
1. Insect Repellent: Used in insect repellent formulations for clothing and mosquito mats.
2. Plasticizer: Previously widely used in the production of plastics to make them more flexible, although its use has declined due to health concerns.
3. Solvent: Acts as a solvent in some organic syntheses.
11.Methyl Salicylate (C8H8O3)
Structure:
Methyl salicylate, also known as wintergreen oil, is an ester formed from the salicylic acid and methanol.
It's characterized by a sweet, minty odor and is a clear liquid at room temperature.
Uses:
1. Flavoring and Fragrance: Widely used for its pleasant odor and taste in foods, beverages, candies, and toothpaste.
2. Pain Relief: Employed in over-the-counter topical creams and ointments for the relief of muscle and joint pain due to its counterirritant properties.
3. Aromatherapy and Cosmetics: Utilized in aromatherapy products and cosmetics for its scent and cooling sensation.
12. Acetylsalicylic Acid (Aspirin) (C9H8O4)
Structure:
Acetylsalicylic acid, commonly known as aspirin, is an ester derived from the acetylation of the hydroxyl group of salicylic acid.
It features an acetoxy group (COCH3) in place of the hydroxyl group on the benzene ring of salicylic acid.
Uses:
1. Pain Relief: Aspirin is a widely used analgesic for the relief of pain, fever, and inflammation.
2. Cardiovascular: Low doses are used as an antiplatelet agent to prevent heart attacks and strokes.
Anti-inflammatory: It has anti-inflammatory properties, making it useful in the treatment of conditions like rheumatoid arthritis.