Question

1. determine an equation for mass number. mass number = protons + ? neutrons electrons 0 / 1 submissions used

Explanation:

The mass number of an atom is the sum of the number of protons and neutrons in its nucleus. Electrons have negligible mass compared to protons and neutrons, so they are not included in the mass number calculation. Thus, the missing part in the equation "Mass Number = Protons +?" is Neutrons.

Answer:

Neutrons (the option "Neutrons" is the correct one to fill in the blank, so the answer is the "Neutrons" option, which would be represented as the button or choice labeled "Neutrons" in the given interface. If we consider the options as presented, the correct one is the "Neutrons" option, so the answer is the "Neutrons" choice, e.g., if we were to box the correct label, it would be \boxed{Neutrons} but following the multiple - choice style here, the correct option is the "Neutrons" one among the two given buttons.)