A sample of metallic element X, weighing 4.315 g, combines with 0.4810 L of Cl2 gas (at

Question:

A sample of metallic element X, weighing 4.315 g, combines with 0.4810 L of Cl2 gas (at normal pressure and 20.0oC) to form the metal chloride with the formula XCl. If the density of Cl2 gas under these conditions is 2.948 g/L, what is the mass of the chlorine? The atomic mass of chlorine is 35.453 amu. What is the atomic mass of X? What is the identity of X?