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Average Atomic Mass Practice. Silicon has 3 isotopes with the following % abundances. Si-28, 92.23% Si-29, 4.67% Si-30, 3.10% Calculate silicon’s average atomic mass. . Answer. (28 x 0.9223) + (29 x 0.0467) + (30 x .031) = 28.11 amu. % Abundance Practice.
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Average Atomic Mass Practice Silicon has 3 isotopes with the following % abundances. Si-28, 92.23% Si-29, 4.67% Si-30, 3.10% Calculate silicon’s average atomic mass.
Answer (28 x 0.9223) + (29 x 0.0467) + (30 x .031) = 28.11 amu
% Abundance Practice • Silver, Ag, exists as 2 isotopes, Ag-107 and Ag-109. Calculate the % abundance for each isotope of silver.
Answer 107.8682 = (x)(107) + (1-x)(109) X = 0.5659 Ag-107 is 56.59% abundant Ag-109 is 43.41% abundant
2) Lithium exists as 2 isotopes, Li-6 and Li-7. Calculate the % abundance for each isotope of lithium.
Answer 6.94 = (x)(6) + (1-x)(7) X = 0.059 Li-6 is 5.90% abundant Li-7 is 94.10% abundant
Gallium consists of two naturally occurring isotopes with masses of 69 and 71 amu. The average atomic mass of Ga is 69.72 amu. Calculate the abundance of each isotope. • 69Ga = 40% 71Ga = 60% • 69Ga = 69% 71Ga = 31% • 69Ga = 29% 71Ga = 71% • 69Ga = 31% 71Ga = 69% • 69Ga = 64% 71Ga = 36%