The element with a ground state electron configuration of 1s22s22p63s2 is an alkaline earth metal. The element with a ground state electron configuration of [Kr]5s24d105p5 has 10 valence electrons. The electron configuration of 1s22s22p63s23p64s13d2 is an excited state electron configuration for Ti. If an element (abbreviated X) has a ground state electron configuration of [Ne]3s23p4, then the formula of the compound that X forms with magnesium is Mg2X. The ground state electron configuration for the undiscovered element 117 is [Rn]8s26f147d108p5. The ground state electron configuration for Cr is [Ar]4s23d4.