Which of the following gives the correct increasing order of acidic strength in water?

A $C X_{2} H X_{5} OH < C X_{6} H X_{5} OH < CH X_{3} COOH < p - O X_{2} N - C X_{6} H X_{4} - OH < 2,4,6-trinitrophenol$
B $C X_{2} H X_{5} OH < C X_{6} H X_{5} OH < p - O X_{2} N - C X_{6} H X_{4} - OH < 2,4,6-trinitrophenol < CH X_{3} COOH$
C $C X_{2} H X_{5} OH < C X_{6} H X_{5} OH < p - O X_{2} N - C X_{6} H X_{4} - OH < CH X_{3} COOH < 2,4,6-trinitrophenol$
D $C X_{6} H X_{5} OH < C X_{2} H X_{5} OH < p - O X_{2} N - C X_{6} H X_{4} - OH < CH X_{3} COOH < 2,4,6-trinitrophenol$

Answer: C

pKa values: ethanol 15.9, phenol 10.0, 4-nitrophenol 7.15, acetic acid 4.76, 2,4,6-trinitrophenol 0.4. Acid strength increases as pKa falls, which gives ethanol < phenol < 4-nitrophenol < acetic acid < picric acid.

Practice General Organic Chemistry II: Acids and Bases More on Acidic strength of organic compounds and pKa comparisons

Previous questionNext question

Which of the following gives the correct increasing order of acidic strength in water?

Answer: C

More questions on Acidic strength of organic compounds and pKa comparisons