AP BIOLOGY

Detailed explanation-1: -A selenium atom has six valence electrons.

Detailed explanation-2: -Answer and Explanation: Valence electrons are electrons in the outermost energy level of an atom. Selenium is in the fourth period, so its valence electrons are in the fourth energy level. Selenium is in the oxygen family, also known as group 16, therefore it has 6 valence electrons.

Detailed explanation-3: -Oxygen, like all the other elements in group 16, has six valence electrons.

Detailed explanation-4: -For example, oxygen has six valence electrons, two in the 2s subshell and four in the 2p subshell.

Detailed explanation-5: -It has an atomic number of 6. That means a carbon atom has 6 protons, 6 neutrons, and 6 electrons.