__________ is used as an 'entrainer' for the separation of acetic acid-water mixture by distillation.

ANS:C - Butyl acetate

Butyl acetate, also known as butyl ethanoate, is an organic compound with the chemical formula CH₃COO(CH₂)₃CH₃. It is an ester, specifically the butyl ester of acetic acid. Butyl acetate is a colorless liquid with a fruity odor, similar to that of apples or bananas, which makes it commonly used as a flavoring agent in foods and beverages. Here are some key points about butyl acetate:

1. Chemical Structure: Butyl acetate consists of a butyl group (a four-carbon alkyl chain) attached to the carbonyl carbon of an acetate group (CH₃COO-). The butyl group contains four carbon atoms in a linear chain, with three methylene (-CH₂-) groups and a terminal methyl (-CH₃) group.
2. Physical Properties: Butyl acetate is a volatile liquid with a boiling point of around 126°C and a density of approximately 0.88 g/cm³ at room temperature. It is miscible with most organic solvents but only slightly soluble in water. Butyl acetate has a characteristic fruity odor, which makes it useful in various industrial applications, such as in paints, coatings, and adhesives, where it is used as a solvent.
3. Applications:
   • Solvent: Butyl acetate is primarily used as a solvent in various industries, including paint and coatings, printing inks, adhesives, and chemical synthesis. It dissolves a wide range of organic compounds and is valued for its low toxicity, good solvency power, and pleasant odor.
   • Flavoring Agent: Due to its fruity odor, butyl acetate is used as a flavoring agent in the food and beverage industry. It imparts a sweet, fruity taste and aroma to products such as candies, ice cream, and soft drinks.
   • Nail Polish Remover: Butyl acetate is a common ingredient in nail polish removers due to its ability to dissolve and remove nail polish effectively.
4. Safety: Butyl acetate is generally considered to be relatively safe for use in industry and consumer products when handled properly. However, it can pose health risks if inhaled or ingested in large quantities. Exposure to high concentrations of butyl acetate vapor may cause irritation of the eyes, nose, and throat, as well as dizziness and headache. Therefore, appropriate safety precautions should be taken when handling this compound.