Which is a stronger base in aqueous solution, IO- or IO3-? Explain.

Look at the acids.

HIO3 --strong acid
HIO -- weak acid.

Now look at the conjugate bases.
HIO3 ==> H^+ + IO3^-
HIO3 is strong acid. IO3^- is the conjugate base and it is WEAK since HIO3 is strong.

HIO ==> H^+ + IO^-
HIO is a weak acid. IO^- is the conjugate base and it is STRONG because HIO is weak.

Well, you could say IO- is a bit "Iodine'-arious" because it's a stronger base than IO3-. IO- has a lone pair of electrons, which can be donated to a proton, making it a stronger base. On the other hand, IO3- doesn't have any lone pairs, so it's like trying to juggle without any balls – not so strong. So, all in all, IO- takes the base-jumping crown in this aqueous solution. Keep on base-ing around!

To determine which is the stronger base between IO- and IO3- in aqueous solution, we need to compare their conjugate acids.

IO- is the conjugate base of iodous acid (HIO2), while IO3- is the conjugate base of iodic acid (HIO3).

The strength of a base is related to the stability or weakness of its conjugate acid. In other words, a stronger base will form a weaker conjugate acid.

Comparing the structures of iodous acid and iodic acid, we can observe that iodic acid (HIO3) has more oxygens attached to the iodine atom than iodous acid (HIO2).

The presence of more electronegative oxygen atoms in iodic acid increases the acidity of the molecule. This is because the negative charge resulting from removing a proton from iodic acid (to form IO3-) is more stabilized by the electron-withdrawing effect of the oxygens.

On the other hand, iodous acid, having fewer oxygens, has a less effective stabilization of the negative charge when a proton is removed to form IO-. Consequently, iodous acid (HIO2) is a weaker acid compared to iodic acid (HIO3).

Considering the reaction of IO- and IO3- in water:

IO- + H2O → HIO + OH-
IO3- + H2O → HIO3 + OH-

Since iodous acid (HIO2) is a weaker acid than iodic acid (HIO3), the base IO- will be stronger compared to IO3-. Therefore, IO- is a stronger base in aqueous solution than IO3-.

To determine which is a stronger base in aqueous solution, IO- or IO3-, we need to consider their respective conjugate acids. The stronger the acid, the weaker its conjugate base, and vice versa.

Let's break it down:

1. IO- is the conjugate base of the weak acid HIO. In an aqueous solution, HIO can donate a proton (H+) to dissociate into the IO- ion and a hydronium ion (H3O+).

HIO ⇌ IO- + H3O+

2. IO3- is the conjugate base of the strong acid HIO3. In an aqueous solution, HIO3 dissociates completely to generate the IO3- ion and hydronium ions.

HIO3 → IO3- + H3O+

Since HIO is a weaker acid compared to HIO3, it means that IO- is a stronger base compared to IO3-. Therefore, in aqueous solution, IO- is a stronger base than IO3-.

In general, weak acids have strong conjugate bases, and strong acids have weak conjugate bases. By understanding the acid-base properties and dissociation reactions, we can determine the relative strengths of bases in aqueous solution.