Respuesta :
Answer:
10
Explanation:
(20) which is the atomic mass you subtract it from the mass number to get 10
Answer:
10
Explanation
Atomic number is the amount of protons, there is an equal amount of neutrons as protons. Atomic mass is about 1 (Dalton) for both a proton and neutron. Electrons are so tiny they barely affect atomic mass at all.
