Question

The correct order of increasing basicity of the following is
$H _{2} O , OH ^{-}, CH _{3} OH , CH _{3} O ^{-}$

• A. $CH _{3} OH < H _{2} O < OH ^{-}< CH _{3} O ^{-}$
• B. $H _{2} O < CH _{3} OH < CH _{3} O ^{-}< OH ^{-}$
• C. $H _{2} O < CH _{3} OH < OH ^{-}< CH _{3} O ^{-}$
• D. $CH _{3} OH < H _{2} O < CH _{3} O ^{-}< OH ^{-}$

Answer 1

Answer: (C)

Basicity depends upon the availability of lone pair of electrons for donation. Between $H _{2} O$ and $CH _{3} OH$, the later is more basic because of the presence of electron donating $- CH _{3}$ group.
Thus, $CH _{3} OH > H _{2} O$ (basicity order)
Conjugate base of weaker acid is strong.
Thus, $CH _{3} O ^{-}> OH ^{-}$(basicity order)
Hence, the increasing order of basicity is
$CH _{3} O ^{-}> OH ^{-}> CH _{3} OH > H _{2} O$