Q9-9P a - Organic Chemistry (Mcmurry)

Question

The of acetone, ${\mathbf{pk}}_{\mathbf{a}}$of acetone, ${\mathbf{CH}}_{\mathbf{3}}{\mathbf{COCH}}_{\mathbf{3}}$ is 19.3. Which of the following bases is strong enough to deprotonate acetone?

(a) KOH  (pk_a of H₂O 15.7)

Step-by-Step Solution

Answer

Answer

Not strong enough to deprotonate acetone due to less than acetone.

Step1: pk a of acetone

pk_ais a number that describes the acidity of the molecule lower the value of pk_a stronger will be acidic and easily donate a proton and higher the value of pk_a weaker will be the acid and stronger will be the conjugate base.

 Acetone has high value of pk_a then KOH

Step2: pk a of NaHCO 3

pk_a of KOH is less than acetone so that KOH is the strong acid and the weak conjugate base than acetone due to the weak conjugate base KOH not able to deprotonate the acetone.