Final answer:
The acids HX, HY, and HZ can be ordered by increasing acid strength based on the basicity of their potassium salt solutions as HZ < HY < HX, with HZ being the weakest and HX the strongest acid.
Step-by-step explanation:
The question asks for the arrangement of acids HX, HY, and HZ in order of increasing acid strength based on the pH values of their potassium salt solutions. To answer this, consider that a higher pH value indicates a weaker acid, because the solution is more basic. Thus, if the pH of KX is 7.0 (neutral), the pH of KY is 8.0 (basic), and the pH of KZ is 9.0 (more basic), then HZ is the weakest acid and HX is the strongest. Accordingly, the order of increasing acid strength is HZ < HY < HX.