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Element X has two naturally occurring isotopes, 65X (isotopic mass 65.3410 amu, abundance 31.87%) and 67X (isotopic mass 66.9519 amu, abundance 68.13%). Calculate the atomic mass of element X.

User Tim Bodeit
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1 Answer

6 votes

Answer:


m_X=66.4385amu

Step-by-step explanation:

Hello there!

In this case, according to the given information for this problem, it turns out possible for us to calculate the average atomic mass of the element by multiplying the mass of each isotope by its percent abundance and then add up the results, just as shown below:


65.3410amu*0.3187=20.8242amu\\\\66.9519amu*0.6813=45.6143amu\\\\m_X=20.8242amu+45.6143amu\\\\m_X=66.4385amu

Regards!

User Gray Kemmey
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