Answer
$K_b = 6.31\times 10^{- 5}$
Work Step by Step
1. Calculate the Ka value:
$K_a = 10^{-pKa}$
$K_a = 10^{- 9.8}$
$K_a = 1.585 \times 10^{- 10}$
2. Since $(CH_3)_3N$ is the conjugate base of $(CH_3)_3NH^+$ , we can calculate its kb by using this equation:
$K_a * K_b = K_w = 10^{-14}$
$ 1.585\times 10^{- 10} * K_b = 10^{-14}$
$K_b = \frac{10^{-14}}{ 1.585\times 10^{- 10}}$
$K_b = 6.31\times 10^{- 5}$
