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What are the structural differences between alcohols and phenols, and how do those differences affect their physical properties and reactivity in different chemical reactions? Provide specific examples and explain the underlying chemical principles.

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Alcohols and phenols are both organic compounds containing a hydroxyl  -OH  functional group. However, they differ in the structure of the carbon atoms to which the hydroxyl group is attached, which in turn affects their physical properties and reactivity in chemical reactions.Structural Differences:1. Alcohols: In alcohols, the hydroxyl group is attached to an aliphatic  saturated or unsaturated  carbon atom. Alcohols can be classified as primary  1 , secondary  2 , or tertiary  3  depending on the number of carbon atoms bonded to the carbon atom bearing the hydroxyl group. For example, ethanol  CH3CH2OH  is a primary alcohol, while isopropanol  CH3CHOHCH3  is a secondary alcohol.2. Phenols: In phenols, the hydroxyl group is directly attached to a carbon atom in an aromatic ring, typically a benzene ring. The simplest example is phenol itself  C6H5OH .Physical Properties:1. Boiling Point: Both alcohols and phenols exhibit hydrogen bonding due to the presence of the hydroxyl group, which leads to higher boiling points compared to hydrocarbons of similar molecular weight. However, phenols generally have higher boiling points than alcohols because the aromatic ring in phenols allows for stronger intermolecular interactions, such as - stacking and dipole-dipole interactions.2. Solubility: Alcohols and phenols can form hydrogen bonds with water, making them soluble in water to some extent. However, the solubility of alcohols decreases with increasing carbon chain length, as the hydrocarbon portion becomes more dominant and hydrophobic. Phenols are generally less soluble in water than alcohols due to the hydrophobic nature of the aromatic ring.Reactivity:1. Acidity: Phenols are generally more acidic than alcohols. When the hydroxyl group loses a proton  H+ , phenols form phenoxide ions  C6H5O- , which are stabilized by resonance within the aromatic ring. In contrast, alkoxide ions  RO-  formed by alcohols are not resonance-stabilized, making alcohols less acidic.2. Nucleophilic Substitution Reactions: Alcohols can undergo nucleophilic substitution reactions, such as SN1 and SN2, depending on the substrate's structure  primary, secondary, or tertiary . Phenols, on the other hand, do not readily undergo nucleophilic substitution reactions due to the partial double bond character between the hydroxyl group and the aromatic ring, which makes the C-O bond less susceptible to nucleophilic attack.3. Electrophilic Aromatic Substitution Reactions: Phenols are highly reactive towards electrophilic aromatic substitution reactions due to the electron-donating nature of the hydroxyl group, which activates the benzene ring. Alcohols do not undergo electrophilic aromatic substitution reactions, as they lack an aromatic ring.4. Oxidation: Primary and secondary alcohols can be oxidized to form aldehydes, ketones, or carboxylic acids, depending on the reaction conditions. Tertiary alcohols are resistant to oxidation. Phenols, however, do not undergo oxidation reactions under the same conditions as alcohols, since the hydroxyl group is bonded to an aromatic carbon.In summary, the structural differences between alcohols and phenols, mainly the nature of the carbon atom to which the hydroxyl group is attached, significantly affect their physical properties and reactivity in chemical reactions. Phenols are generally more acidic and more reactive towards electrophilic aromatic substitution reactions, while alcohols can undergo nucleophilic substitution and oxidation reactions.

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