Given are cyclohexanol `(I)`, acetic acid `(II),2,4,6-`trinitrophenol `(III)` and phenol `(IV)`. In these the order of decreasing acidic character will be:

Options

A. IIIgtIVgtIIgtI
B. IIIgtIIgtIVgtI
C. IIgtIIIgtIgtIV
D. IIgtIIIgtIVgtI

Answer

B

Explanation

due to strong -I and -R-effect of the three `-NO_(2)` groups, 2,4,6-trinitrophenol (III) is more acidic than `CH_(3)COOH` (II). Further, due to greater resonance stabilization of acetate ion over phenoxide ion, acetic acid (II) is a stronger acid than phenol (IV). since alcohols are less acidic than phenols. therefore, cyclohexanol (I) is less acidic than phenol (IV). thus, the overall acidic character decreases in the order:
2,4,6-tribromophenol (III)gtacetic acid(II)gtphenol (IV)gtcyclohexanol (I), i.e., option (b) is correct.