Lithium forms compounds which are used in dry cells, storage batteries, and in high-temperature lubricants. It has two naturally occurring isotopes, ⁶Li (isotopic mass = 6.015123 amu) and ⁷Li (isotopic mass = 7.016005 amu). Lithium has an atomic mass of 6.9412 amu. What is the percent abundance of lithium-6? A) 92.53% B) 86.65% C) 49.47% D) 7.47% E) 6.015%

Question

Quizplus · Accepted Answer

The atomic mass of lithium is a weighted average of its isotopes. Using the equation: (6.015123 * x) + (7.016005 * (1-x)) = 6.9412, solving for x gives the percent abundance of lithium-6 as approximately 7.47%.

Lithium Forms Compounds Which Are Used in Dry Cells, Storage