Question

1. How many protons, neutrons and electrons does the isotope Au-195 have?

Answer 1

We Know, Atomic number of Gold (Au) = 79
1) Number of Protons = Atomic number = 79
    Number of Electrons = Number of Protons = 79     
    Number of Neutrons = mass number - Atomic number = 195-79 = 116

2) Atomic number = 79  [ written on top of the element ]
    Mass number = 195   [ written on bottom of the element ]

Hope this helps!