How many neutrons are present in a nucleus?

Question

How many neutrons are present in a  nucleus?

Quizplus · Accepted Answer

The number next to the element symbol in the question represents its atomic number, which is the number of protons in the nucleus. To find the number of neutrons, we subtract the atomic number from the mass number (the number after the element symbol). Therefore, the mass number of the given nucleus is 233 and the atomic number is 91. Subtracting 91 from 233 gives us 142, which is the number of neutrons present in the nucleus. Therefore, the best choice is B.

How Many Neutrons Are Present in a Nucleus