The electron affinities, in kJ>mol, for the group 1B and

QUESTION:

The electron affinities, in kJ>mol, for the group 1B and group 2B metals are as follows: Hg > 0 Au 223 Cd > 0 Ag 126 Zn > 0 Cu 119 (a) Why are the electron affinities of the group 2B elements greater than zero? (b) Why do the electron affinities of the group 1B elements become more negative as we move down the group? [Hint: Examine the trends in the electron affinities of other groups as we proceed down the periodic table.]