Answer :
Final answer:
A nitrogen element with an atomic mass of 15 amu and a charge of -3 has 7 protons, 10 electrons, and 8 neutrons.
Explanation:
If an element of nitrogen has an atomic mass of 15 amu and a charge of -3, we can determine how many protons, neutrons, and electrons it has. The atomic number of nitrogen (which defines the number of protons in an atom) is 7. Since the nitrogen is an ion with a charge of -3 (N³⁻), it has three more electrons than protons, which equates to 10 electrons. The atomic mass of nitrogen is most commonly 14 amu (since 14N is the most common isotope), but for a nitrogen atom with an atomic mass of 15 amu, we can infer it's an isotope of nitrogen (15N). Using the atomic mass, we can calculate the number of neutrons as atomic mass - atomic number, which is 15 - 7 = 8 neutrons.
