What is the mass of an atom that contains two positively charged nuclides, and two neutrally charged nuclides? What is the atom?

1 Answer
Jul 21, 2017

Well, the conventional helium NUCLEUS comprises 4 massive particles.....

Explanation:

Atomic mass is to a very good first approx. NUCLEAR mass, i.e. the number of massive nuclear particles. The helium nucleus has 2 protons, 2 positively charged, massive particles, Z=2, and this is what defines the nucleus as helium. The common helium isotope also contains 2 neutrons to give 4He. Capisce?