Chapter 19

a) There is one valence electron in a \(\mathrm{H}\) atom. What is the average ionization energy of the one valence electron in \(\mathrm{H}\) ? (Note that this is a very easy question because there is only one valence electron!) b) There are two valence electrons in a He atom. What is the average ionization energy of the two valence electrons in He? (Again, an easy question because both valence electrons have the same IE!) c) Which atom, \(\mathrm{H}\) or He, holds its valence electron(s) "more tightly" on average? Explain your reasoning.

Use the shell model of atoms and the concept of core charge to explain why the AVEE of atoms generally increases from left to right across a period.

Use the shell model of atoms and the concept of core charge to explain why the AVEE of atoms generally decreases from top to bottom down a group.

In terms of AVEE, explain why Na is more likely to form \(\mathrm{Na}^{+}\) than \(\mathrm{O}\) is to form \(\mathrm{O}^{+}\)

Describe the trend in EN moving left to right across a period of the periodic table.

Describe the trend in EN moving down a group of the periodic table.