Why does chlorine dissolve in water, but iodine doesn't?

[pritikamehra]

1) Is it something to do with the fact that chlorine is more electronegative than iodine is, therefore the chlorine nucleus would feel some force of attraction for the slightly positive hydrogen atom in the water molecule?

 

2) One website mentioned that chlorine was soluble because its electrons were susceptible to creating induced dipoles -- but using that logic, wouldn't iodine be more soluble as it has a greater sized electron cloud?!

 

3) Also, the Cl-Cl bond is supposedly stronger than the I-I bond.

 

Any ideas?

[elementcollector1]

Iodine actually does dissolve in water to some extent, turning the liquid yellow.

The reason halogens can dissolve in water is because they disassociate into their respective acid and oxy-acid, in chlorine's case HCl and HOCl. This reaction is reversible.

Curiously, bromine is very highly soluble in water, whereas chlorine and iodine are not. This may have something to do with bromine being a liquid (and thus being miscible with water where a gas and a solid might not be). However, that's speculation.

[mostafaghayad]

Actually, The answer for this question is very simple, Iodine doesn't dissolve in water because Iodine is a non-polar solute, whereas water is polar solvent. Same thing applies in case of water and oil, why doesn't water mix with oil? thats because water is a polar solvent, while oil is a non-polar solvent. Briefly, polar solutes dissolve in polar solvents, whereas non-polar solutes dissolve in non-polar solvents.

[John Cuthber]

Actually, The answer for this question is very simple, Iodine doesn't dissolve in water because Iodine is a non-polar solute, whereas water is polar solvent. Same thing applies in case of water and oil, why doesn't water mix with oil? thats because water is a polar solvent, while oil is a non-polar solvent. Briefly, polar solutes dissolve in polar solvents, whereas non-polar solutes dissolve in non-polar solvents.

You seem to have missed half the question.

Chlorine dissolves quite well in water, even though, like iodine, it is non-polar.