Final answer:
For acid HX with a very large Ka, at equilibrium, the concentration of H+ ions will be significantly larger than the concentration of non-ionized HX, which will be nearly zero. So the correcct option is A.
Step-by-step explanation:
When considering the acid HX with a very large Ka, at equilibrium, the concentration of H+ will be larger than that of HX. The acid-ionization constant, Ka, indicates the extent of ionization of the acid. A very large Ka value suggests that the acid ionizes almost completely in solution. Thus, for a strong acid like HX with a large Ka, we would typically find that at equilibrium, virtually all of the HX has dissociated into H+ and X- ions. Therefore, the concentration of H+ ions will greatly exceed the concentration of non-ionized HX because the latter is essentially zero, as strong acids are considered 100% ionized in solution.