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.


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?