Hi. I'm having a hard time solving this problem. I have to find the identity of element X in the following reaction: [tex]XCl_2~+~Cl_2~-->~XCl_4[/tex] knowing that 10 grams of [tex]XCl_2[/tex] + 2.55 grams of [tex]Cl_2[/tex] produces 12.55 grams of [tex]XCl_4[/tex]. Now, I thought about doing mass percent composition that way I could know how much Cl there was in relation to the element X but I don't know any way to do that. I'm stuck. Any ideas?