Question

Given are cyclohexanol(I), acetic acid (II), $2,4,6$-trinitrophenol (III) and phenol (IV), in these the decreasing acidic character will be:

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

Answer 1

The correct option is B III $>$ II $>$ IV $>$ I

The decreasing order of acidic character-

$III>II>IV>I$

In $2,4,6$-trinitrophenol, $-N{O}_2$ group show the $-M$ effect, it draws the electrons from the ring and makes the ring more acidic,

In phenol, $-OH$ group show $-M$ effect also,

Order Of -M Effect is given as:$-N{O}_2>-OH$

In cyclohexanol, In the absence of resonance, $-OH$ will show $+I$ effect and activated the ring with electrons that make the ring less acidic.

The correct option is [B].