### If an atom has 18 electrons, how many protons doe…

00:29
Problem 72
Case Western Reserve University
Problem 69

Xenon An isotope of xenon has an atomic number of
54 and contains 77 neutrons. What is the xenon isotope's

Mass number of the isotope $=131$ amu.

## Discussion

You must be signed in to discuss.

## Video Transcript

the element in this question as 55 protons and 31 nutrients, the addition of protons and neutrons together forms the full mass. So 55 plus 31 is 131 a M U Judiciary answer.