The total mass of the protons in an atom of gold-198 is approximately

(1) 79 atomic mass units

(2) 119 atomic mass units

(3) 198 atomic mass units

(4) 277 atomic mass units

Verified Answer :

Gold has an atomic number of 79
Protons have a relative mass of 1
Gold-198 is a radioactive isotope of gold, which means it has a different number of neutrons, but the same number of protons and electrons
So the answer isĀ (1) 79 atomic mass units