The following pictures represent aqueous solutions of three acids HA (A = X, Y, or Z), with water molecules omitted for clarity. Unshaded spheres represent hydrogen atoms or ions and gray spheres represent A atoms or ions. Which of the three is the strongest acid, and which is the weakest?
◦ HZ is the strongest acid and HY is the weakest acid.
◦ HY is the strongest acid and HZ is the weakest acid.
◦ HY is the strongest acid and HX is the weakest acid.
◦ HX is the strongest acid and HY is the weakest acid.