Question

Among the following compounds, the strongest acid is

• A. $HC\equiv CH$
• B. $N{H}_3$
• C. $C{H}_2=C{H}_2$
• D. $C{H}_{3}OH$

Answer 1

The correct option is D $C{H}_{3}OH$

$\text{Acidic strength}\propto \text{stability of conjugate base}\propto \text{E.N. of atom containing hydrogen}$
the correct order of stability of conjugate base is
$C{H}_3{O}^{-}>CH\equiv C^{-}>N{H}_2^{-}>C{H}_2=C{H}^{-}$
sp hybrid carbon is more electronegative than nitrogen.
Hence, correct stability order is $C{H}_{3}OH>CH\equiv CH>N{H}_3>C{H}_2=C{H}_2$