How many neutrons are in an isotope of gold-197?

33

Hydrogen has three isotopes:Hydrogen-1= 1 proton and no neutronsHydrogen-2 (deuterium) =1 proton and 1 neutronHydrogen-3 (tritium) = 1 proton and 2 neutrons

its according to the number of isotopes

8 neutrons..

The "25" part is the mass number of the isotope. The mass number is the sum of the number of protons and the number of neutrons. You are trying to find out the number of neutrons, but we already know...