For each of the following atoms, write down a ground state electronic configuration and indicate which electrons are core and which are valence: (a) Na, (b) F, (c) N, (d) Sc. Draw energy level diagrams (see Fig. 1.15) to represent the ground state electronic configurations of the atoms in problem 1.26.

Write down the ground state electronic configuration of boron, and give a set of quantum numbers that uniquely defines each electron. Write down (with reasoning) the ground state electronic configurations of (a) Li, (b) O, (c) S, (d) Ca, (e) Ti, (f) Al. Draw energy level diagrams to show the ground state electronic configurations of only the valence electrons in an atom of (a) F, (b) Al and (c) Mg.