How many neutrons are in the nucleus of an atom of 200Hg?

Question

Quizplus · Accepted Answer

The atomic number of Hg (mercury) is 80, which means it has 80 protons. The mass number of 200 tells us that the total number of protons and neutrons in the nucleus is 200. Therefore, we can subtract the atomic number (number of protons) from the mass number (total number of protons and neutrons) to find the number of neutrons: 200 - 80 = 120. So, there are 120 neutrons in the nucleus of an atom of 200Hg.

How Many Neutrons Are in the Nucleus of an Atom