Recall that atoms gain or lose electrons to become ions. So, an ion has a different number of electrons than its corresponding neutral atom. Positive ions have lost electrons, and negative ions have gained electrons. The table includes the electron configuration of several ions. Complete the rows for magnesium and oxygen (oxide) ions by identifying the correct ion charge, electron configuration, and neutral atom with the same configuration as the ion. You may need to use online resources or the periodic table to determine the correct ion charges. Select the correct answer from each drop-down menu to complete the table.​