The ionization energies of two unknown third-period elements (A and B) are shown in the graphs below. From the graphs, we can see a large jump in energy between IE1 and IE2 for element A, below, and between IE1 and IE2 for element B. Select the correct answers from the dropdown menus: 8000, 7000, Third ionization, 6000, 6910, energy, 5000, 7730 kJ/mol, 4000, Second ionization, 3000, energy, 4560, 2000, First, 1000, ionization energy, 1450, 0, 496, 738, A, B.
The identity of element A is Na because it has 1 valence electron and [Select].
The identity of element B is Mg because it has 2 valence electrons and [Select].