Answer
(a) $A_2Y$ is the strongest electrolyte because it is totally ionized, and $A_2X$ is the weakest, because it is the one with the lowest ionization.
(b) A ions concentration: $0.700M$. Y ions concentration: $0.350M$.
(c) $25$ $\%$.
Work Step by Step
(a) The separated spheres represent the ions, and the group of spheres represent the molecules.
Therefore, the group with the higher concentration of separated spheres $(A_2Y)$ is the most ionized one, which makes it the stronger electrolyte.
The one with the lower ions concentration is the $A_2X$, which makes it the weaker electrolyte.
(b) Each $A_2Y$ has 2 $A$ ions and 1 $Y$ ion. Since it is completely ionized:
$\frac{0.350 mol(A_2Y)}{1 L} \times \frac{2 mol(A^{n+})}{1 mol (A_2Y)} = 0.700M(A^{n+})$
$\frac{0.350 mol(A_2Y)}{1 L} \times \frac {1 mol(Y^{2n-})}{1 mol (A_2Y)} = 0.350M(Y^{2n-})$
(c) As we can observe, the solution has 4 $A_2X$, but only one of them is ionized:
Percent ionization = $\frac{1}{4} \times 100 \% = 25\%$
