Final answer:
Small cations are more likely to share edges or faces than large cations due to their ability to fit into interstitial spaces between anions, leading to a denser packing in the crystal lattice. Their smaller size allows for stronger electrostatic attractions and higher lattice energy in compounds with large anions.
Step-by-step explanation:
The question: "_____ cations are more likely to share edges or faces than _____ cations," is pertaining to the arrangement of ions in a crystal lattice and their relative sizes. The correct answer is A. Small, large. Small cations are more likely to share edges or faces than large cations. This is because small cations can more easily fit into the interstitial spaces between anions, allowing for a more dense packing and thus a tendency for edge or face-sharing. Large cations have a more difficult time fitting closely together which can lead to arrangements with fewer shared edges or faces.
When considering lattice energy, the smaller the cation and the larger the anion, the greater the lattice energy will be, assuming a similar arrangement of ions. This is because smaller cations can get closer to the anions, increasing the electrostatic attractions between them, and thus, increasing the lattice energy.