Consider the skeletal structures of the four hydrocarbons shown below. Which of these hydrocarbons will be oxidized to the corresponding alcohol upon treatment with potassium permanganate ( KMnO ₄ )?

Step-by-step solution

Alkanes are generally resistant to oxidation by strong oxidizing agents like KMnO ₄ . However, alkanes containing a tertiary hydrogen atom can be oxidized to the corresponding tertiary alcohol by KMnO ₄ . Let us analyze the given hydrocarbons: Compound I (n-pentane) contains only primary ( 1^ ) and secondary ( 2^ ) hydrogen atoms. Compound II (2-methylbutane) contains a tertiary ( 3^ ) hydrogen atom at the second carbon. Compound III (2,2-dimethylpropane) contains only primary ( 1^ ) hydrogen atoms. Compound IV (cy