Each are effectively a hydrocarbon (that is to say a compound consisting of only hydrogen and carbon) where one or more of the the hydrogen elements has been substituted for something else.
A COOH item in the case of Acetic Acid, 2 Cl2 items in the case of tetrachloroethylene and an OK in the case of ethanol.
A COOH item in the case of Acetic Acid, 2 Cl2 items in the case of tetrachloroethylene and an OK in the case of ethanol.
