Question

A compound that is composed of molybdenum (Mo) and oxygen (O) was produced in a lab by heating molybdenum over a Bunsen burner. The following data was collected: Mass of crucible: 38.26 g Mass of crucible and molybdenum: 39.52 g Mass of crucible and molybdenum oxide: 39.84 g Solve for the empirical formula of the compound, showing (or explaining in complete sentences) your calculations

Answer 1

To get the mass of molybdenum in the crucible, you subtract the mass of the crucible from the mass of the crucible and molybdenum:
39.52g - 38.26g = 1.26g

To get the mass of molybdenum oxide in the crucible, you subtract the mass of the crucible from the mass of the crucible and molybdenum oxide:
39.84g - 38.26g = 1.58g

To get the mass of oxide, you subtract the mass of molybdenum from the mass of molybdenum oxide:
1.58g - 1.26g = 0.32g

To get the number of moles of molybdenum you divide the mass of molybdenum by its molecular mass:
1.26g/96 = 0.01 moles

To get the number of moles of oxide, divide the mass of oxide by its molecular mass:
0.32g/16 = 0.02 moles

There are twice as many moles of oxygen so the empirical formula is: MoO2. HOPE THIS HELPS