Benzene ring in phenol is expected to give the characteristic substitution or replacement reactions, i.e., halogenation, nitration, sulphonation, alkylation, etc. In these reactions, the attacking reagent is electrophile. The phenolic group activates the ortho and para positions in the ring due to conjugation. Disubstitution reactions are quite fast as the electron density in the ring has increased considerably. Phenols do not respond to nucleophilic substitution reactions as it is influenced by phenolic group.

Secondary alcohol among the following is:

Choose the correct answer from the options given below:

D and E only

The correct answer is (1) D and E only.

Secondary alcohols are a type of alcohol in which the carbon atom bearing the hydroxyl (-OH) group is bonded to two other carbon atoms. The general structure of a secondary alcohol can be represented as follows:

\[ \text{R}_1 - \text{C}(\text{OH}) - \text{R}_2 \]

Here, \(\text{C}(\text{OH})\) represents the carbon atom with the hydroxyl group, and \(\text{R}_1\) and \(\text{R}_2\) are organic groups or hydrogen atoms bonded to the carbon atom.

An example of secondary alcohol is isopropanol (or 2-propanol), which has the molecular formula \( \text{CH}_3 - \text{CHOH} - \text{CH}_3 \).

In contrast, primary alcohols have the hydroxyl group attached to a carbon atom that is bonded to only one other carbon atom, while tertiary alcohols have the hydroxyl group attached to a carbon atom that is bonded to three other carbon atoms.

The classification of alcohols into primary, secondary, or tertiary is based on the carbon atom to which the hydroxyl group is attached, and it is important in understanding the reactivity and properties of these compounds in various chemical reactions.