What is correct order for acidity of water, phenol and ethanol
Correct answer: A. C6H5OH > H2O > C2H5OH
- A. C6H5OH > H2O > C2H5OH
- B. H2O > C2H5OH > C6H5OH
- C. C6H5OH > C2H5OH > H2O
- D. H2O > C6H5OH > C2H5OH
Explanation
The correct order of acidity is C6H5OH > H2O > C2H5OH. Phenol is the most acidic because its phenoxide ion is stabilized by resonance, which allows for better delocalization of negative charge. Water is more acidic than ethanol because the hydroxide ion it forms is more stable than the ethoxide ion due to the lack of electron-donating alkyl groups that destabilize the alkoxide ion. The other options incorrectly order the acidity of these substances, either by misplacing water's position relative to phenol or ethanol.
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About Alcohols and Phenols
Alcohols are classified as primary, secondary or tertiary and studied through their hydrogen bonding, acidity, oxidation and reactions with active metals, acids and halogenating agents. Phenols require separate treatment because the hydroxyl group is attached to an aromatic ring, making their acidity and electrophilic substitution different from ordinary alcohols.
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