Which of the following are carboxylic acids:

C2H4O2, C2H4O, C2H6O, C3H6O2?

Carboxylic acids are compounds where one or more hydrogen atoms are replaced by the -COOH group:


Note that every carboxylic acid contains 2 O (oxygen) atoms. The carboxylic acids with no other functional groups have the molecular formula CnH2nO2.


Using this, one can say that C2H4O2 (ethanoic acid) and C3H6O2 (propanoic acid) are carboxylic acids.


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