Which ester is produced from methanol and ethanoic acid?

Which ester is produced from methanol and ethanoic acid?

• A. Ethyl ethanoate
• B. Methyl ethanoate
• C. Propyl ethanoate
• D. Methyl formate

Answer: (B)

Esters are formed when an alcohol reacts with a carboxylic acid in a condensation reaction, where the -OH from the acid is replaced by the alkoxy group from the alcohol. Here, methanol supplies the methyl part (-O-CH3) and ethanoic acid provides the acyl part (CH3CO-). Putting them together gives methyl ethanoate (methyl acetate), with the structure CH3COOCH3. If a different alcohol were used, you'd get a different ester—for example, ethanol would give ethyl ethanoate, and formic acid would give methyl formate.

Esters are formed when an alcohol reacts with a carboxylic acid in a condensation reaction, where the -OH from the acid is replaced by the alkoxy group from the alcohol. Here, methanol supplies the methyl part (-O-CH3) and ethanoic acid provides the acyl part (CH3CO-). Putting them together gives methyl ethanoate (methyl acetate), with the structure CH3COOCH3. If a different alcohol were used, you'd get a different ester—for example, ethanol would give ethyl ethanoate, and formic acid would give methyl formate.