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If copper metal is a mixture two isotopes Cu-63 mass=62.9298 u and Cu-65, mass=64.9279 u. Calculate the % abundances if the molar mass of copper is 64.546 g/mole.

2007-04-09 10:45:15 · 2 answers · asked by mrfame1017 3 in Science & Mathematics ➔ Chemistry

2 answers

62.9298 + 64.9279(1-x) = 64.546

64.9279 - 1.9981x = 64.546

-1.9981x = -0.3819

x = .19113

19.113 % Cu-63, 80.887 % Cu-65

2007-04-09 11:05:10 · answer #1 · answered by Huy T 2 · 0⤊ 0⤋

set up an algebraic equation.

If x = % abundance of Cu-63, then 100-x = % abundance of Cu-55

Now calculate the weighted average and solve for X

62.9298 X + 64.9279 (100-X) = 64.546

2007-04-09 11:08:03 · answer #2 · answered by reb1240 7 · 0⤊ 0⤋