Would you expect Li_2S to conduct electricity in its solid state?

• A. Yes, because it is a strong electrolyte.
• B. No, because it is a covalent compound.
• C. Yes, because it contains mobile ions in the solid state.
• D. No, because the ions are fixed in the crystal lattice and cannot move.

Answer: (D)

Verified step by step guidance

1. Understand that electrical conductivity in solids depends on the presence of mobile charged particles, such as ions or electrons, that can move freely to carry charge.
2. Recognize that Li_2S is an ionic compound composed of Li^+ and S^{2-} ions arranged in a crystal lattice structure.
3. Recall that in the solid state, these ions are held rigidly in place within the crystal lattice and cannot move freely.
4. Since the ions are fixed and immobile in the solid lattice, Li_2S cannot conduct electricity in its solid form.
5. Note that ionic compounds like Li_2S typically conduct electricity only when molten or dissolved in water, where ions are free to move.