Question

Which is the decreasing order of acidity in the following compound?

$C{H}_{3}C{H}_{2}OH\left(I\right)$
$C{F}_{3}C{H}_{2}OH\left(II\right)$
$CC{l}_3-C{H}_{3}OH\left(iii\right)$
$(N{O}_2{)}_{3}C-C{H}_{2}OH(IV)$

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

Answer 1

The correct option is D IV > II > III > I

Order of acidity of a compound depends on the stability of its conjugate base.

Conjugate Base of I : $C{H}_{3}C{H}_2{O}^{-}$

Conjugate Base of II : $C{F}_{3}C{H}_2{O}^{-}$

Conjugate Base of III : $CC{l}_3-C{H}_3{O}^{-}$

Conjugate Base of IV : $(N{O}_2{)}_{3}C-C{H}_2{O}^{-}$

Order of stability of conjugate base : $IV>II>III>I$

So, is the order of acidity.

Hence, Option "D" is the correct answer.