Identify the number of neutrons in one atom of sulfur with an atomic mass number of 34 amu.

18 neutrons

Explanation:

The atomic number of sulfur is 16.Atomic number indicates the number of protons in the nucleus of an atom.Neutrons are found in the nucleus of an atom together with the protons and account for the difference in the mass number among isotopes of an element.The sum of neutrons and protons gives the atomic mass number of an element.Therefore; given the mass number and the atomic number(number of protons) we can calculate the number of neutrons.

Number of protons = 16

Mass number = 34

Number of neutrons = mass of number - number of protons

                                   = 34 - 16

                                  = 18 neutrons

The answer to this question is a