An atom with 7 protons has which property?

• A. Atomic Mass
• B. Neutron Count
• C. Electron Count
• D. Atomic Number

Answer: (D)

The number of protons in the nucleus defines the atomic number, which identifies the element. With 7 protons, the atom’s atomic number is 7, corresponding to nitrogen. This property is fixed for a given element and stays the same across all its atoms, whereas other properties can vary: atomic mass depends on neutrons, neutron count can differ among isotopes, and electron count can change if the atom is charged. So the property tied to having 7 protons is the atomic number.