The average atomic mass of lithium is 6.941 amu.Lithium has two naturally occurring isotopes,⁶Li (7.52%)and ⁷Li (92.48%).The mass of ⁶Li is 6.0151 amu.What is the isotopic mass of ⁷Li?

Question

Quizplus · Accepted Answer

We can use the formula for calculating average atomic mass: average atomic mass = (abundance of isotope 1 x mass of isotope 1) + (abundance of isotope 2 x mass of isotope 2) Substituting the given values: 6.941 amu = (0.0752 x 6.0151 amu) + (0.9248 x mass of ⁷Li) Solving for the unknown, we get: Mass of ⁷Li = (6.941 amu - 0.0752 x 6.0151 amu) / 0.9248 Mass of ⁷Li = 7.016 amu Therefore, the isotopic mass of ⁷Li is 7.016 amu.

The Average Atomic Mass of Lithium Is 6