Final answer:
Carboxylic acids react with alcohols to produce esters through esterification, and esters are often responsible for the characteristic fragrances of fruits. Carboxylic acids contribute a sour taste to foods such as citrus fruits and vinegar.
Step-by-step explanation:
The statement that carboxylic acids react with alcohols to form esters is true. This reaction is known as an esterification reaction, where a carboxylic acid and an alcohol combine to produce an ester and water. For example, acetic acid reacts with ethanol to form ethyl acetate, an ester, which is commonly used as a solvent and in the production of paints and varnishes. Esters are known for their pleasant fragrances and are often responsible for the sweet smells of fruits such as apples and bananas, whereas carboxylic acids such as citric acid and acetic acid are known for imparting a sour taste to foods.
It is incorrect to say that carboxylic acids are responsible for the sweet taste and smell of fruits; this characteristic is typically attributed to esters. Similarly, while esters do participate in reactions under high temperatures, forming an acid anhydride is not a condensation reaction they typically undergo themselves, but rather a result of a reaction between a carboxylic acid and an ester under specific conditions. Lastly, it is not esters but rather certain acids like lactic acid that give sourdough bread its sour taste.