Problem: Lithium has two naturally occurring isotopes: Li-6 (natural abundance 7.5%; mass 6.0151 amu) and Li-7 (natural abundance 92.5%; mass 7.0160 amu).Without doing any calculations, determine which mass is closest to the atomic mass of Li.

FREE Expert Solution

We have to determine which of the two isotopes of lithium has the mass closest to its average atomic mass.


The percentage by which an isotope of an element occurs with other isotopes of the same element, is called natural abundance.


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Problem Details

Lithium has two naturally occurring isotopes: Li-6 (natural abundance 7.5%; mass 6.0151 amu) and Li-7 (natural abundance 92.5%; mass 7.0160 amu).

Without doing any calculations, determine which mass is closest to the atomic mass of Li.

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