A hypothetical element,E,has two stable isotopes:
E-46 = 46.046 u 64.08%
E-51 = 50.826 u 35.92%
What is the average atom weight of the element?
A)47.76 u
B)48.44 u
C)49.11 u
D)48.50 u
E)47.44 u

Question

Quizplus · Accepted Answer

The average atomic weight of an element is the weighted average of the atomic weights of its isotopes, where the weights are the relative abundances of the isotopes. In this case, the average atomic weight of element E is:(46.046 u * 0.6408) + (50.826 u * 0.3592) = 47.76 uTherefore, the correct answer is A) 47.76 u.

A Hypothetical Element,E,has Two Stable Isotopes