Question
Question: Which among the following compounds has lowest acidic strength?...
Which among the following compounds has lowest acidic strength?
A
Ethyl alcohol
B
t-Butyl alcohol
C
Phenol
D
p-nitrophenol
Answer
t-Butyl alcohol
Explanation
Solution
The acidic strength is inversely proportional to the pKa value. A higher pKa indicates a lower acidic strength.
- Ethyl alcohol: pKa ≈ 16
- t-Butyl alcohol: pKa ≈ 19
- Phenol: pKa ≈ 10
- p-Nitrophenol: pKa ≈ 7
Since t-Butyl alcohol has the highest pKa (~19), it is the least acidic.