Question

Which of the following has highest $pK_b$ value?

• A. $(CH_3)_3CNH_2$
• B. $NH_3$
• C. $(CH_3)_2NH$
• D. $CH_3NH_2$

Answer 1

Answer: (B)

$NH_3$

Answer 2

Higher the basicity, lower is the $pK_b$ value.Since $NH_3$ is the weakest base, hence it has highest $pK_b$ value.