Question

The decreasing order of acidity among the compounds, ethanol (I) $2,2,2$-trifluoroethanol (II) trifluroacetic acid and (III) acetic acid (IV) is

• A. III > II > IV > I
• B. IV > III > II > I
• C. I > II > III > IV
• D. III > IV > II > I

Answer 1

Answer: (A)

The acidic character increases with increasing number of electron withdrawing substituents on the a-carbon. Hence, trifluoroacetic acid is more acidic than acetic acid. Further carboxylic acids are more stronger acid than alcohols but due to the presence of three electron withdrawing group ($F$ group), $2,2,2$, trifluoroethanol is more acidic than acetic acid.