Final answer:
The question is incomplete as it lacks the identity of the element X in the compound XCl4. Without knowing X, we cannot calculate the exact mass of the compound. However, the molar mass of Cl is used to exemplify how one would determine the mass of the chlorine atoms in the compound.
Step-by-step explanation:
The question is addressing a chemical compound mass query, which falls under the category of stoichiometry, a key concept in chemistry. The student's question seems to be missing important context, such as the identity of the compound (X needs to be a specific element for us to know its molar mass) and requires clarification to provide a precise mass. However, the molar mass of Cl, which is 35.45 g/mol, is given and can be used to calculate the mass of Cl in a compound XCl4. Assuming X represents an element and knowing that there are four Cl atoms, we can calculate the mass for these four Cl atoms as 4 x 35.45 g/mol = 141.8 g/mol for just the Cl part. Without knowing what X is, we cannot give a total mass for the compound.
As an example, if X were carbon (C), with a molar mass of 12.01 g/mol, then the molar mass of CCl4 would be 12.01 g/mol (for C) + 141.8 g/mol (for 4Cl) = 153.81 g/mol. This example serves to illustrate how the mass of a compound can be calculated using the molar mass of its constituent atoms.