Final answer:
To add a hydroxyl group to an alkene in a Markovnikov fashion alternatively, one can use the acid-catalyzed hydration of alkenes, where strong acids like sulfuric acid are used as a catalyst, forming a carbocation which is then attacked by water, leading to an alcohol product.
Step-by-step explanation:
The student is asking for an alternative method to add OH (hydroxyl group) to an alkene in a Markovnikov fashion, besides the use of water (H2O) and hydronium ion (H3O+). A common method to achieve this is via the acid-catalyzed hydration of alkenes. In this reaction, a catalyst, usually a strong acid like sulfuric acid (H2SO4), is employed.
To achieve Markovnikov addition of OH across an alkene, the alkene first reacts with the acid to form a carbocation intermediate. The water then acts as a nucleophile and adds to the positively charged carbon atom of the carbocation. A proton is subsequently removed by another water molecule, resulting in the formation of an alcohol. This process is typically favorable since water acts as a nucleophile in a high concentration relative to the conjugate base of the acid.