Question

Rhenium (Re) is made up of 37.4% 185Re and 62.6% 187Re. The atomic mass of 185Re is 184.953 amu. The atomic mass of 187Re is 186.958 amu. What is the average atomic mass of rhenium?

Answer 1

Answer: The answer is 186.208 amu

Step-by-step explanation:

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Answer 2

To calculate the average mass of the element, we take the summation of the product of the isotope and the percent abundance. We calculate as follows:

Average atomic mass = .374 ( 184.953 amu ) + .626 ( 186.958 amu ) = 186.208 amu

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