Lithium has two naturally occurring isotopes,⁶Li and ⁷Li.The atomic weight of lithium is 6.941.Which of the following statements concerning the relative abundance of each isotope is correct? A) The abundance of ⁷Li is greater than ⁶Li. B) The abundance of ⁷Li is less than ⁶Li. C) The abundance of ⁶Li is equal to the abundance of ⁷Li. D) Not enough data is provided to determine the correct answer. E) Based on the atomic mass,only ⁷Li occurs naturally.

Question

Quizplus · Accepted Answer

The atomic weight of lithium is a weighted average of the atomic masses of its isotopes, taking into account their relative abundances. Since the atomic weight of lithium is closer to the atomic weight of S1U1P7S1S1P0Li than S1U1P6S1S1P0Li, it must mean that S1U1P7S1S1P0Li is more abundant than S1U1P6S1S1P0Li. Therefore, choice A is correct.

Lithium Has Two Naturally Occurring Isotopes,6Li and 7Li

Lithium Has Two Naturally Occurring Isotopes,⁶Li and ⁷Li