What are the numbers of protons and neutrons in: Gold-198, Potassium-39, Uranium-232 and Plutonium-244?

Answer 1

First of all, Atomic # is the number of protons and the # of neutrons is atomic mass (the numbers in you hyphen notation) - atomic #.

Gold (Au) has an atomic number of 79
Protons=79
Neutrons=198-79
Neutrons=119

Potassium (K) has an atomic number of 19
Protons=19
Neutrons=39-19
Neutrons= 20

Uranium (U) has an atomic number of 92
Protons=92
Neurtons= 232-92
Neutrons= 140

Plutonium (Pu) has an atomic number of 94
Protons=94
Neutrons=244-94
Neutrons= 150

Answer 2

Au-198: 79 p, 119 n
K-39: 19 p, 20 n
U-232: 92 p, 140 n
Pu-244: 94 p, 150 n

Answer 3

The numbers after the names of the elements are the mass numbers/A/. A=Z+N, where Z= numbers of protons and N=numbers of neutrons. You can find Z in the periodic table and it's equal to the position(number) of the elements there (eg. Z/S/ = 16). That's how you'll find out the N (N=A-Z).
It wouldn't be difficult for me to solve your problem, but it's better to do it yourself!