Why is chlorine more reactive than iodine?

1 Answer
Nov 8, 2016

Chlorine has a higher effective nuclear charge, and therefore should be more oxidizing than iodine.

Explanation:

The nuclear charge of chlorine is less shielded by intervening electrons. Thus chlorine gas should be a better oxidant.

If we turn to reduction potentials, which we should do as scientists because scientists must utilize quantitative data, we find:

1/2Cl_2 + e^(-) rarr Cl^- E^@ = 1.36

1/2I_2 + e^(-) rarr I^- E^@ = 0.54

How is this consistent with the given proposition?