1.883 Grams of copper reacted with excess sulfur to form an unknown Copper sulfide. The reaction creates 2.308 grams of an unknown Copper Sulfide. What I am trying to find Is the empirical formula of the Copper Sulfide. It is either, Copper(I) Sulfide or Copper(II) sulfide. I don't need the answer but rather an explanation of how to solve this problem.

You just calculated that the heat of fusion for chloromethane is 6400 j/mol. the heat of fusion for hydrogen is 120 j/mol.? which of the following account for this difference? more than one correcta. chloromethane can absorb more energy at the same temperature. b. hydrogen has stronger intermolecular forces than chloromethane. c. hydrogen molecules can pack more closely than chloromethane molecules. d. chloromethane experiences dipole-dipole interactions. e. chloromethane has a higher molar mass than hydrogen.