Please Help me!
Caporic acid (C5H11COOH) is found in small amounts in cocunut and palm oils and is used in making artificial flavors. A saturated solution of the acid contains 11 g/L and has a pH of 2.94. Calculate Ka for the acid.

Question

Please Help me!
Caporic acid (C5H11COOH)  is found in small amounts in cocunut and palm oils and is used in making artificial flavors. A saturated solution of the acid contains 11 g/L and has a pH of 2.94. Calculate Ka for the acid.

anonymous · Answer

Use your equilibrium constant expression:$$\frac{[{\rm H}^+][{\rm A}^-]}{[{\rm HA}]} = K_a$$where [H+] is the molarity of H+, which you can get from the pH, [A-] is the molarity of the anion -- which is going to be essentially equal to the molarity of H+, since they are released in equal amounts by the dissociation of the acid -- and [HA] is the molarity of the undissociated acid, which you can calculate from the mass concentration and the molar mass of the acid.

anonymous · Answer

Thank you, but I still do not understand, is that the answer or can you explain what I have to do?