Chapter 2, Problem 79IAE

From densities of the lines in the mass spectrum of krypton gas, the following observations were made:
• Somewhat more than 50% of the atoms were krypton-84.
• The numbers of krypton-82 and krypton-83 atoms were essentially equal.
• The number of krypton-86 atoms was 1.50 times as great as the number of krypton-82 atoms.
• The number of krypton-80 atoms was 19.6% of the number of krypton-82 atoms.
• The number of krypton-78 atoms was 3.0% of the number of krypton-82 atoms.

The masses of the isotopes are
$\text{K}\text{r, 77}\text{.9204 u}$  $\text{K}\text{r, 79}\text{.9164 u}$  $\text{K}\text{r, 81}\text{.9135 u}$
$\text{K}\text{r, 77}\text{.9141 u}$  $\text{K}\text{r, 83}\text{.9115 u}$  $\text{K}\text{r, 85}\text{.9106 u}$

The weighted-average atomic mass of Kr is 83.80. Use these data to calculate the percent isotopic abundances of the krypton isotopes.