Chapter 16, Problem 26E

Caproic acid, ${\text{HC}}_{\text{g}}{\text{H}}_{\text{11}}{\text{O}}_{\text{2}}$ , found in small amounts in coconut and palm oils, is used in making artificial flavors. A saturated aqueous solution of the acid contains 11 g/L and has pH=2.94. Calculate $K_g$ for the acid.

${\text{HC}}_{\text{6}}{\text{H}}_{\text{11}}{\text{O}}_{\text{2}}{\text{+H}}_{\text{2}}\text{O}\rightleftharpoons {\text{H}}_3{\text{O+C}}_{\text{6}}{\text{H}}_{\text{11}}{\text{O}}_{\text{2}}^{\text{-}}-{\text{K}}_{\text{a}}\text{=?}$