An atom with an atomic number of 9 and a mass number of 19 would have an atomic mass of approximately

Question

Quizplus · Accepted Answer

The atomic mass of an element is the sum of the protons and neutrons in the nucleus. The atomic number of 9 indicates that there are 9 protons in the nucleus. The mass number of 19 indicates that there are 19 total nucleons (protons + neutrons) in the nucleus. Therefore, the atom must have 10 neutrons (19-9). Adding the 9 protons and 10 neutrons, we get an atomic mass of 19 daltons.

An Atom with an Atomic Number of 9 and a Mass