-caproic acid, , found in coconut and palm oil is used in making artificial flavours, has solubility — Ionic Equilibrium Chemistry Question

💡 Solution & Explanation

The molar mass of caproic acid ($\text{C}_5\text{H}_{11}\text{COOH}$) is $(5 \times 12 + 11) + 45 = 116\text{ g/mol}$. Its molar concentration is $C = 11.6\text{ g/L} / 116\text{ g/mol} = 0.1\text{ M}$. Given $\text{pH} = 3.0$, $[\text{H}^+] = 10^{-3}\text{ M}$. The acid dissociation constant is $K_a \approx \frac{[\text{H}^+]^2}{C} = \frac{(10^{-3})^2}{0.1} = \frac{10^{-6}}{0.1} = 10^{-5}$.