Chapter 2 - Chemical Formulas and Composition Stoichiometrhy - Exercises - Atomic and Weight Formulas - Page 75: 31

The ratio of masses present is 1.76 g Ba 0.487 g F = 3.614 or 3.614 g Ba 1.0 g F . Based on the formula BaF2, this ratio represents 1 atom Ba 2 atoms F . So the atomic mass ratio of Ba/F is AW Ba AW F or 3.614 1.0/2 = 7.228 From a table of atomic weights, AW Ba AW F = 137.33 amu 19.00 amu = 7.228 This calculation could not be done without knowledge of the formula or some other knowledge of the relative numbers of atoms present

The ratio of masses present is 1.76 g Ba 0.487 g F = 3.614 or 3.614 g Ba 1.0 g F . Based on the formula BaF2, this ratio represents 1 atom Ba 2 atoms F . So the atomic mass ratio of Ba/F is AW Ba AW F or 3.614 1.0/2 = 7.228 From a table of atomic weights, AW Ba AW F = 137.33 amu 19.00 amu = 7.228 This calculation could not be done without knowledge of the formula or some other knowledge of the relative numbers of atoms present