A solid substance X has a vapor pressure of 300mm Hg at 25oC and does not conduct electricity. Solid substance Y has an undetectably small vapor pressure at 25oC and is a good electrical conductor. Which of the following statements is consistent with these data?
X is a molecular solid and Y is an ionic solid.
X is an ionic solid and Y is a metallic solid.
X is a network covalent solid and Y is an ionic solid.
X is a molecular solid and Y is a metallic solid.
X is a network covalent solid and Y is a metallic solid.