[jjkwest1]

A certain oxygen atom has the electron configuration 1s²2s²2p_x²2p_y². How many unpaired electrons are present? Is this an excited state of oxygen? In going from this state to the ground state would energy be release or absorbed?

I get that there are no unpaired electrons but can someone explain to me how you can tell this is in an excited state since that the answer in the book.