The average atomic mass of zinc is 65.39 amu. Given the data in the following table, what is the natural abundance of ⁶⁶Zn?

Question

Quizplus · Accepted Answer

To find the natural abundance of ⁶⁶Zn, we need to use the weighted average formula: Average atomic mass = (mass1 x % abundance1) + (mass2 x % abundance2) + ... Let x be the natural abundance of ⁶⁶Zn. Then, we can set up the equation: 65.39 amu = (63.9291 amu x 48.89%) + (65.9260 amu x x) + (66.9271 amu x 4.11%) + (67.9249 amu x 18.56%) + (69.9253 amu x 0.62%) Solving for x gives us x = 27.83%, which is choice A.

The Average Atomic Mass of Zinc Is 65