The increasing order of pK a for the following phenols is (A) 2,4-Dinitrophenol (B) 4-Nitrophenol (C) 2,4,5-Trimethylphenol (D) Phenol (E) 3-Chlorophenol Choose the correct answer from the option given below :

Step-by-step solution

Order of acidity for following phenol is Increasing order of pK a means most acidic will be placed first. - &#160; M groups at ortho and para position increases acidic strength in phenol. Hence, (A) is most acidic. + M , Hyperconjugation, + I decreases K a Value of 2,4,5-Trimethylphenol. Hence (C), is least acidity. So, the order of pK a value is (A) < (B )< (E)< (D)< (C).