What is the total number of protons and neutrons in the nuclide ""_35^80Br?

Jun 10, 2017

Well, there are $\text{45 neutrons}$...........
The atomic number, $Z$, of bromine is $35$. And thus the subscript in ""_35^80Br is quite superfluous.......because the symbol $B r$ specifies $35$ nuclear charges........
We write ""^80Br. Because the superscripted mass number is equal to the SUM of nuclear protons and neutrons, the number of neutrons is equal to $80 - Z = 80 - 35 = 45$ $\text{neutrons..........}$