Chapter 16 Principles of Chemical Reactivity: The Chemistry of Acids and Bases - Study Questions - Page 629b: 32

$K_a = 6.667\times 10^{- 6}$

1. We can use this formula to find the ka or kb of a conjugate acid-base pair. $K_b * K_a = K_w = 10^{-14}$ $ 1.5\times 10^{- 9} * K_a = 10^{-14}$ $K_a = \frac{10^{-14}}{ 1.5\times 10^{- 9}}$ $K_a = 6.667\times 10^{- 6}$