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Two stable isotopes of lithium .(3)^(6)L...

Two stable isotopes of lithium `._(3)^(6)Li` and `._(3)^(7)Li` have respective abundances of 7.5% and 92.5%. These isotopes have masses 6.01512 u and7.01600 u, respectively. Find the atomic mass of lithium.

Text Solution

Verified by Experts

Atomic weight = Weight average of the isotopes.
`= (6.01512xx7.5+7.01600xx92.5)/((7.5+92.5))`
`= (45.1134+648.98)/(100)`
`= 6.9414`
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Knowledge Check

  • Two stable isotopes of lithium ""_(3)^(6)Li and ""_(3)^(7)Li have respective abundances of 7.5% and 92.5%. These isotopes have masses 6.01512u and 7.01600u, respectively. Then the atomic mass of lithium is

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