Hi,so this monday we had chemistry class again and also because we room learning around halogens our teacher stated some acids and also she described why some of them space stronger than other. She obtained to the allude of to compare HClO4, HClO3, HClO2 and HClO. She arranged them in this stimulate in to decrease acidicity explaining why. As I uncovered out end time, she is oversimplifying things, in this short article I will shot to present why they space in this order.

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Almost prefer water, the photo of perchloric acid. (HClO4)

So below we have four acids (to make it faster I will compare only very first and last one). Both room same other than that there are three an ext oxygens in HClO4 and the oxidation variety of Cl is VII on the left and I on the right. Now this needs to be the reason for various properties.

In all of those molecules Cl is the middle one, which way that all oxygens are connected to the with double bond, except one with only simple one which has hydrogen on the other side.


The picture shows the structure of these molecules.

So as you probably recognize water has what is dubbed “dipole moment”. This is a term that is offered for molecule that have partiall fee on one side and also the other charge ~ above the various other side.

This has very interesting properties however what is crucial is the HClO4 has this too, and much more than HClO because there space oxygen ion which have actually charge that -II make chlorine in the middle of them a many “ripped off” since there space those oxygens with higher electronegativity that room trying to acquire those electron to get on the configuration of noble gases.

Now before the conclusion we must clear the end the an interpretation of acidic molecule. Such a molecule is acid when it is good at providing H+, so currently the concern is, why is HClO4 far better in providing H+ than HClO?

So the key lies in what happens when these acids rest up. As soon as HClO4 i do not care ClO4- over there is not so lot stress into obtaining the hydrogen back because delocalized electron from the various other oxygens <1> have the right to ease it increase making the molecule an ext stable when in HClO loser only one of two donors of oxygen make the molecule want it ago a LOT.


Electron withdrawal boosts strength.

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If you space not sure about this, ask me in the comment or examine out the resources that ns used.


Resources: 1|2|3|4|5|6

<1> yes oxygens here have actually all two free electron bag which room doing part wonders!