Final answer:
In oxidizing primary alcohols, concentrated acid is often added first to facilitate the reaction, with water added afterwards if necessary to drive the equilibrium forward or perform hydrolysis of esters.
Step-by-step explanation:
Oxidation of Alcohols and Addition of Reagents
The process of oxidizing alcohols varies depending on the desired outcome. When oxidizing primary alcohols, the initial step leads to the formation of aldehydes, which can further oxidize to form carboxylic acids. To drive these reactions forward, either an excess of alcohol is used, or water is removed, especially when performing alcoholysis reactions. In instances where the reverse reaction is necessary, called hydrolysis of esters, water is added in excess.
For acid-catalyzed hydrolysis of esters, the preference of either water or alcohol addition can affect the direction of the equilibrium. In general, when conducting oxidation reactions where concentrated acids are utilized, such as sulfuric acid, the acid is typically added first to protonate the alcohol, making it a better leaving group, facilitating the subsequent chemical transformation.
In summary, whether you add concentrated acid first or water depends on the specific conditions and goals of the oxidation reaction. As a rule of thumb for oxidations with concentrated acids, the acid is usually introduced before any water to optimize the reaction conditions.