Question

In the field of chemistry, specifically in atomic mass calculations, if iodine has three isotopes - iodine with a mass of 127 amu and an abundance of 80%, iodine with a mass of 128 amu and an abundance of 3%, and the last isotope with a mass of 126 amu and an abundance of 17%, what is the average atomic mass of iodine? A) 127.1 amu B) 127.5 amu C) 126.3 amu D) 128.0 amu

Answer 1

Answer: A) 127.1 amu

Step-by-step explanation:

To find the average atomic mass of an element, we multiply each isotope by its abundance, add them all together, then divide by 100.

`((127*80)+(128*3)+(126*17))/(100)` = 126.9 amu

The closest choice to my answer is A) 127.1 amu, which makes sense because iodine-127 has the highest abundance at 80%, and the isotope with the highest abundance is always the closest to the average atomic mass of the element.

I hope this helps! :)