Question

an atom containing 7 protons, 8 neutrons, and 7 electrons:

• cannot exist.
• is charge-neutral.
• is an ion.
• is an oxygen atom.
• none of the above

Explanation:

To determine the correct option, we analyze the atom's properties:

• Protons (positive charge) = 7, Electrons (negative charge) = 7. Since the number of protons equals the number of electrons, the atom has a net charge of 0 (charge - neutral).
• An ion has a net charge (unequal protons and electrons), so it is not an ion.
• Oxygen has 8 protons, but this atom has 7 protons (so it is a nitrogen isotope, not oxygen).
• Atoms with 7 protons (nitrogen) and 8 neutrons (mass number 15) do exist.

Answer:

B. is charge - neutral.