Final answer:
Oxygen is the atom with the given electron configuration. It has 6 valence electrons and is in the second energy level.
Step-by-step explanation:
The electron configuration of Oxygen (O) atom is 1s²2s²2p⁴. Oxygen has six valence electrons in the second energy level, (2s²2p⁴). The anion O² is formed when two electrons are gained in the valence shell.
The resulting electron configuration, 1s²2s²2p⁶, which is also identical to the configuration for the noble gas neon.