Question

Uranium has 146 neutrons; therefore its mass number is which of the following?

Answer 1

Okay First you will need to find the atomic number of the element or isotope. The atomic number is the number of protons in an element, and never changes. :)

2nd, find the number of neutrons in the nucleus. The number of neutrons can vary within an atom—while they are the same element, they are different isotopes of that element.

3rd, add the proton and neutron count. This is the atomic mass of that atom. :D

Number of Protons = Atomic Number

Number of Electrons = Number of Protons = Atomic Number

Number of Neutrons = Mass Number - Atomic Number