Chapter 2.5, Problem 1CP

Boron has two naturally occurring isotopes, ${}^{\text{10}}\text{B an}{\text{d}}^{\text{11}}\text{B,}$ which have masses 10.0129 and 11.0093 amu, respectively. Given the average atomic mass of boron (10.81 amu), determine the percent abundance of each isotope.

$\begin{array}{l}\text{a})\\ 50{\%}^{10}{\text{B, 50\% }}^{\text{11}}\text{B}\\ \text{b)}\\ {\text{20\% }}^{\text{10}}{\text{B, 80\% }}^{\text{11}}\text{B}\\ \text{c)}\\ {\text{98\% }}^{\text{10}}{\text{B, 2\% }}^{\text{11}}\text{B}\\ \text{d)}\\ {\text{93\% }}^{\text{10}}{\text{B, 7\% }}^{\text{11}}\text{B}\\ \text{e)}\\ {\text{22\% }}^{\text{10}}{\text{B, 78\% }}^{\text{11}}\text{B}\end{array}$