The
atomic mass of an element is a result of the weighted average of the
masses of its corresponding isotopes.
We are given:
Ag-107: mass of 106.905 amu, 52 percent abundance
Ag-109: mass of 108.905 amu,
48 percent abundance
To be able to calculate the atomic mass of
silver, we multiply the percent abundances of the isotopes by their
respective atomic masses. Then, we add,
Atomic mass = (Atomic Mass of Ag-107) (%
Abundance) + (Atomic Mass of Ag-109) (% Abundance )
Substituting the given values, we have
Atomic mass = 106.905 (.52) + 108.905 (.48)
Atomic mass = 107.865 amu
Therefore, the atomic mass of silver would be 107.865 amu.
