Final answer:
The question does not provide enough information to determine the ratio of the radii of aluminum to lead spheres, as it lacks numerical values and context on atomic versus ionic radii.
Step-by-step explanation:
When comparing the radius of a lead sphere with that of an aluminum sphere, we must consider the information given about their ionic states. Unfortunately, the question does not provide specific numeric values to calculate the exact ratio of the radii of aluminum to lead spheres. Without numerical values or additional context like whether the comparison is based on the atomic radii or the ionic radii post-reaction, the ratio can't be determined strictly from the information at hand.
In the typical chemistry context, the ionic radius of aluminum in its cationic form (Al3+) is indeed smaller than its atomic radius because it loses electrons and the remaining electrons are more strongly attracted to the nucleus. Conversely, the ionic radius of a sulfur anion (S2-) is larger than its atomic radius because the addition of electrons causes greater electron-electron repulsion and thus an increase in size.