<span>Answer: B. Ionic solids have higher melting points than molecular solids.
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This is because the rest are false, as solids are able to melt, and do have melting points. Also, not all solids have the same melting points.
D. Sublimation is a solid turning directly into a gas
I think you want to ask the complete ionic equation and net ionic equation. For complete ionic equation: 3Ba2+ + 6Cl- + 2Al3+ + 3SO42- -->3BaSO4 + 2Al3+ + 6Cl-. For net ionic equation: 3Ba2+ + 3SO42- -->3BaSO4.