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Will
Will asked in Science & MathematicsChemistry · 7 years ago

Help with chemistry homework?

Copper can be found as 2 isotopes, 63-copper and 65-copper, in the ratio of 70/30. Find the average mass number of copper.

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  • Roger the Mole
    Lv 7
    7 years ago
    Favorite Answer

    Supposing the atomic masses of the two isotopes to be 63 and 65:

    (0.70 x 63) + (0.30 x 65) = 63.6

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