На рисунке изображены схемы четырех атомов. Черными точками обозначены электроны. Атому 16/8 O соответствует схема

The atomic number of Oxygen (O) is 8, meaning it has 8 protons and in a neutral atom, 8 electrons. The mass number is 16, indicating 16 nucleons (protons + neutrons). The electron configuration of Oxygen is 2 electrons in the first shell and 6 electrons in the second shell. Scheme 4 shows an atom with 2 electrons in the inner shell and 6 electrons in the outer shell, totaling 8 electrons.