A typical oxygen atom has 8 neutrons. In the periodic table, oxygen has an atomic number of 8, which means it has 8 protons in its nucleus. The most common isotope of oxygen, known as oxygen-16, contains 8 neutrons as well. To determine the number of neutrons in an atom, you can subtract the atomic number (the number of protons) from the atomic mass number (the sum of protons and neutrons). For oxygen-16, the atomic mass number is 16, so:
Number of Neutrons = Atomic Mass Number – Atomic Number
Number of Neutrons = 16 – 8 = 8
This calculation confirms that a typical oxygen atom, particularly the most abundant isotope, contains 8 neutrons.