Q9-9P d - Organic Chemistry (Mcmurry)

Question

The pk_a of acetone, CH₃COCH₃, is 19.3. Which of the following bases is strong enough to deprotonate acetone? 

(d) NaOCO₃ ( pk_a of CH₃OH 15.6)

Step-by-Step Solution

Answer

Answer:

Not strong enough to deprotonate acetone due to less pk_a then acetone.

Step 1: pk a of acetone

pk_a is 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 the higher the value of pk_a weaker will be the acid and the stronger will be the conjugate base.

 Acetone has high value of pk_a then NaOCO₃

Step 2: pk a of NaOCO 3

pk_a of NaOCO₃ is less than acetone so that NaOCO₃ is the strong acid and the weak conjugate base than acetone due to weak conjugate base NaOCO₃  not able to deprotonate the   acetone.