The element X has three naturally occurring isotopes. The masses (amu) and % abundances of the isotopes are given in the table below. The average atomic mass of the element is amu.

Question

Quizplus · Accepted Answer

To calculate the average atomic mass, we use the formula:
Average Atomic Mass = (% abundance of isotope 1 x mass of isotope 1) + (% abundance of isotope 2 x mass of isotope 2) + (% abundance of isotope 3 x mass of isotope 3) / 100
Plugging in the values from the table, we get:
Average Atomic Mass = (50.23 x 16.99) + (26.09 x 17.99) + (22.68 x 18.99) / 100 = 17.23 amu
Therefore, the best choice is C, which is closest to the calculated value of 17.23 amu.

The Element X Has Three Naturally Occurring Isotopes