Question

A sample of silver as it occurs in nature is 52.0% of Ag-107 and 48.0% of Ag-109. What is the average atomic mass of silver? (Compare your result with the value given in the periodic table).

A) 106.9051 amu
B) 108.9048 amu
C) 107.86144 amu
D) 55.5232 amu

Answer 1

To find the average atomic mass of silver, calculate the weighted average of the masses of Ag-107 and Ag-109 using their respective percentages as weights. The average atomic mass of silver is 107.86144 amu, which matches the value given in the periodic table.

Step-by-step explanation:

To find the average atomic mass of silver, we need to calculate the weighted average of the masses of Ag-107 and Ag-109, using their respective percentages as weights. The mass of Ag-107 is 106.9051 amu, and the mass of Ag-109 is 108.9048 amu. Using the formula:

Average atomic mass = (%Ag-107 * mass of Ag-107) + (%Ag-109 * mass of Ag-109)

Substituting the values:

Average atomic mass = (0.52 * 106.9051 amu) + (0.48 * 108.9048 amu) = 107.86144 amu.

Comparing this with the value given in the periodic table, the correct answer is C) 107.86144 amu.

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