Question

Choose the correct order of increasing acidic strength of the following compounds.

• A. \text{CH}_3\text{CH}_2\text{OH}<\text{CCL}_3\text{CH}_2\text{OH}<\text{CF}_3\text{CH}_2\text{OH}
• B. \text{CF}_3\text{CH}_2\text{OH}<\text{CCL}_3\text{CH}_2\text{OH}<\text{CH}_3\text{CH}_2\text{OH}
• C. \text{CH}_3\text{CH}_2\text{OH}<\text{CF}_3\text{CH}_2\text{OH}<\text{CCL}_3\text{CH}_2\text{OH}
• D. \text{CCL}_3\text{CH}_2\text{OH}<\text{CF}_3\text{CH}_2\text{OH}<\text{CH}_3\text{CH}_2\text{OH}

Hint:

In alcohols, the acidity increases with the presence of electron-withdrawing groups (such as -Cl or -CF\(_3\)) as they stabilize the negative charge on the oxygen atom after deprotonation.

Answer 1

The Correct Option is A

Acidity in alcohols is influenced by the electron-withdrawing effects of the substituents on the carbon bearing the hydroxyl group. The more electron-withdrawing the substituents, the more they stabilize the negative charge on the oxygen atom after deprotonation, making the compound more acidi(C) 1. CH\(_3\)CH\(_2\)OH (Ethyl alcohol) has no electron-withdrawing group, so it is the least acidic among the given options. 2. CCl\(_3\)CH\(_2\)OH (Trichloroethanol) has three chlorine atoms attached to the carbon. Chlorine is a highly electronegative element, and its electron-withdrawing inductive effect increases the acidity by stabilizing the negative charge on the oxygen after deprotonation. 3. CF\(_3\)CH\(_2\)OH (Trifluoroethanol) has a trifluoromethyl group (-CF\(_3\)) attached to the carbon. The trifluoromethyl group is an even stronger electron-withdrawing group than the chloro group, and it stabilizes the negative charge on oxygen more effectively, making trifluoroethanol the most acidi(C) Therefore, the correct order of increasing acidic strength is: \[ \text{CH}_3\text{CH}_2\text{OH}<\text{CCL}_3\text{CH}_2\text{OH}<\text{CF}_3\text{CH}_2\text{OH} \] Thus, the correct answer is (A)