Question

Anatomic model shows 19 protons 20 neurons and 19 electrons what is the mass number of the atom 19 39.58 20

Answer 1

The mass number of an atom is the sum of the number of protons and neutrons in its nucleus.

In this case, the model shows 19 protons and 20 neurons. The total number of protons and neurons is 19 + 20 = 39.

Therefore, the mass number of the atom is 39.