Final answer:
Oxygen requires two additional electrons to reach an octet, making the correct answer (b) 2. This relates to the ability of oxygen to form two covalent bonds to achieve a full valence shell.
Step-by-step explanation:
The subject of this question is Chemistry, specifically regarding the electronic configuration and bonding of oxygen. To achieve a full octet, an atom must have eight electrons in its valence shell, which is the outermost shell of an atom. Oxygen has a total of six valence electrons, which means it requires two additional electrons to reach an octet. Therefore, the correct answer to the question of how many electrons oxygen requires to reach an octet is (b) 2. This corresponds to the number of covalent bonds oxygen can form, where each bond involves two electrons, one from oxygen and one from another atom.
In the context of forming molecules, beginning with the terminal atoms, each oxygen atom typically needs two additional electrons to complete its octet. These can come from sharing electrons with other atoms to form bonds, or from the gain of electrons in the formation of anions.